diff --git a/include/openthread/instance.h b/include/openthread/instance.h
index 31f36a7ab..4b5b9d15e 100644
--- a/include/openthread/instance.h
+++ b/include/openthread/instance.h
@@ -53,7 +53,7 @@ extern "C" {
  * @note This number versions both OpenThread platform and user APIs.
  *
  */
-#define OPENTHREAD_API_VERSION (346)
+#define OPENTHREAD_API_VERSION (347)
 
 /**
  * @addtogroup api-instance
diff --git a/include/openthread/link.h b/include/openthread/link.h
index 933098c77..5c920db9e 100644
--- a/include/openthread/link.h
+++ b/include/openthread/link.h
@@ -1031,7 +1031,7 @@ otError otLinkSetPromiscuous(otInstance *aInstance, bool aPromiscuous);
  * @returns The CSL channel.
  *
  */
-uint8_t otLinkCslGetChannel(otInstance *aInstance);
+uint8_t otLinkGetCslChannel(otInstance *aInstance);
 
 /**
  * Sets the CSL channel.
@@ -1044,29 +1044,40 @@ uint8_t otLinkCslGetChannel(otInstance *aInstance);
  * @retval OT_ERROR_INVALID_ARGS   Invalid @p aChannel.
  *
  */
-otError otLinkCslSetChannel(otInstance *aInstance, uint8_t aChannel);
+otError otLinkSetCslChannel(otInstance *aInstance, uint8_t aChannel);
 
 /**
- * Gets the CSL period.
+ * Represents CSL period ten symbols unit in microseconds.
  *
- * @param[in]  aInstance      A pointer to an OpenThread instance.
- *
- * @returns The CSL period in units of 10 symbols.
+ * The CSL period (in micro seconds) MUST be a multiple of this value.
  *
  */
-uint16_t otLinkCslGetPeriod(otInstance *aInstance);
+#define OT_LINK_CSL_PERIOD_TEN_SYMBOLS_UNIT_IN_USEC (160)
 
 /**
- * Sets the CSL period in units of 10 symbols. Disable CSL by setting this parameter to `0`.
+ * Gets the CSL period in microseconds
  *
  * @param[in]  aInstance      A pointer to an OpenThread instance.
- * @param[in]  aPeriod        The CSL period in units of 10 symbols.
+ *
+ * @returns The CSL period in microseconds.
+ *
+ */
+uint32_t otLinkGetCslPeriod(otInstance *aInstance);
+
+/**
+ * Sets the CSL period in microseconds. Disable CSL by setting this parameter to `0`.
+ *
+ * The CSL period MUST be a multiple of `OT_LINK_CSL_PERIOD_TEN_SYMBOLS_UNIT_IN_USEC`, otherwise `OT_ERROR_INVALID_ARGS`
+ * is returned.
+ *
+ * @param[in]  aInstance      A pointer to an OpenThread instance.
+ * @param[in]  aPeriod        The CSL period in microseconds.
  *
  * @retval OT_ERROR_NONE           Successfully set the CSL period.
- * @retval OT_ERROR_INVALID_ARGS   Invalid CSL period.
+ * @retval OT_ERROR_INVALID_ARGS   Invalid CSL period
  *
  */
-otError otLinkCslSetPeriod(otInstance *aInstance, uint16_t aPeriod);
+otError otLinkSetCslPeriod(otInstance *aInstance, uint32_t aPeriod);
 
 /**
  * Gets the CSL timeout.
@@ -1076,7 +1087,7 @@ otError otLinkCslSetPeriod(otInstance *aInstance, uint16_t aPeriod);
  * @returns The CSL timeout in seconds.
  *
  */
-uint32_t otLinkCslGetTimeout(otInstance *aInstance);
+uint32_t otLinkGetCslTimeout(otInstance *aInstance);
 
 /**
  * Sets the CSL timeout in seconds.
@@ -1088,7 +1099,7 @@ uint32_t otLinkCslGetTimeout(otInstance *aInstance);
  * @retval OT_ERROR_INVALID_ARGS   Invalid CSL timeout.
  *
  */
-otError otLinkCslSetTimeout(otInstance *aInstance, uint32_t aTimeout);
+otError otLinkSetCslTimeout(otInstance *aInstance, uint32_t aTimeout);
 
 /**
  * Returns the current CCA (Clear Channel Assessment) failure rate.
diff --git a/include/openthread/platform/radio.h b/include/openthread/platform/radio.h
index bb7ef0c3d..35dd46496 100644
--- a/include/openthread/platform/radio.h
+++ b/include/openthread/platform/radio.h
@@ -1059,7 +1059,7 @@ otError otPlatRadioGetCoexMetrics(otInstance *aInstance, otRadioCoexMetrics *aCo
  * Enable or disable CSL receiver.
  *
  * @param[in]  aInstance     The OpenThread instance structure.
- * @param[in]  aCslPeriod    CSL period, 0 for disabling CSL.
+ * @param[in]  aCslPeriod    CSL period, 0 for disabling CSL. CSL period is in unit of 10 symbols.
  * @param[in]  aShortAddr    The short source address of CSL receiver's peer.
  * @param[in]  aExtAddr      The extended source address of CSL receiver's peer.
  *
diff --git a/src/cli/README.md b/src/cli/README.md
index 3ad8e6c20..c0b9217ff 100644
--- a/src/cli/README.md
+++ b/src/cli/README.md
@@ -983,10 +983,12 @@ Done
 
 Get the CSL configuration.
 
+CSL period is shown in microseconds.
+
 ```bash
 > csl
 Channel: 11
-Period: 1000 (in units of 10 symbols), 160ms
+Period: 160000us
 Timeout: 1000s
 Done
 ```
@@ -1002,10 +1004,12 @@ Done
 
 ### csl period \<period\>
 
-Set CSL period in units of 10 symbols. Disable CSL by setting this parameter to `0`.
+Set CSL period in microseconds. Disable CSL by setting this parameter to `0`.
+
+The CSL period MUST be a multiple 160 microseconds which is 802.15.4 "ten symbols time".
 
 ```bash
-> csl period 3000
+> csl period 30000000
 Done
 ```
 
diff --git a/src/cli/cli.cpp b/src/cli/cli.cpp
index 05da53569..e7775fd25 100644
--- a/src/cli/cli.cpp
+++ b/src/cli/cli.cpp
@@ -2327,23 +2327,22 @@ template <> otError Interpreter::Process<Cmd("csl")>(Arg aArgs[])
      * @code
      * csl
      * Channel: 11
-     * Period: 1000 (in units of 10 symbols), 160ms
+     * Period: 160000us
      * Timeout: 1000s
      * Done
      * @endcode
      * @par
      * Gets the CSL configuration.
-     * @sa otLinkCslGetChannel
-     * @sa otLinkCslGetPeriod
-     * @sa otLinkCslGetPeriod
-     * @sa otLinkCslGetTimeout
+     * @sa otLinkGetCslChannel
+     * @sa otLinkGetCslPeriod
+     * @sa otLinkGetCslPeriod
+     * @sa otLinkGetCslTimeout
      */
     if (aArgs[0].IsEmpty())
     {
-        OutputLine("Channel: %u", otLinkCslGetChannel(GetInstancePtr()));
-        OutputLine("Period: %u(in units of 10 symbols), %lums", otLinkCslGetPeriod(GetInstancePtr()),
-                   ToUlong(otLinkCslGetPeriod(GetInstancePtr()) * kUsPerTenSymbols / 1000));
-        OutputLine("Timeout: %lus", ToUlong(otLinkCslGetTimeout(GetInstancePtr())));
+        OutputLine("Channel: %u", otLinkGetCslChannel(GetInstancePtr()));
+        OutputLine("Period: %luus", ToUlong(otLinkGetCslPeriod(GetInstancePtr())));
+        OutputLine("Timeout: %lus", ToUlong(otLinkGetCslTimeout(GetInstancePtr())));
     }
     /**
      * @cli csl channel
@@ -2353,25 +2352,25 @@ template <> otError Interpreter::Process<Cmd("csl")>(Arg aArgs[])
      * @endcode
      * @cparam csl channel @ca{channel}
      * @par api_copy
-     * #otLinkCslSetChannel
+     * #otLinkSetCslChannel
      */
     else if (aArgs[0] == "channel")
     {
-        error = ProcessSet(aArgs + 1, otLinkCslSetChannel);
+        error = ProcessSet(aArgs + 1, otLinkSetCslChannel);
     }
     /**
      * @cli csl period
      * @code
-     * csl period 3000
+     * csl period 3000000
      * Done
      * @endcode
      * @cparam csl period @ca{period}
      * @par api_copy
-     * #otLinkCslSetPeriod
+     * #otLinkSetCslPeriod
      */
     else if (aArgs[0] == "period")
     {
-        error = ProcessSet(aArgs + 1, otLinkCslSetPeriod);
+        error = ProcessSet(aArgs + 1, otLinkSetCslPeriod);
     }
     /**
      * @cli csl timeout
@@ -2381,11 +2380,11 @@ template <> otError Interpreter::Process<Cmd("csl")>(Arg aArgs[])
      * @endcode
      * @cparam csl timeout @ca{timeout}
      * @par api_copy
-     * #otLinkCslSetTimeout
+     * #otLinkSetCslTimeout
      */
     else if (aArgs[0] == "timeout")
     {
-        error = ProcessSet(aArgs + 1, otLinkCslSetTimeout);
+        error = ProcessSet(aArgs + 1, otLinkSetCslTimeout);
     }
     else
     {
diff --git a/src/core/api/link_api.cpp b/src/core/api/link_api.cpp
index 7a97d4ce0..f342627a9 100644
--- a/src/core/api/link_api.cpp
+++ b/src/core/api/link_api.cpp
@@ -395,9 +395,9 @@ bool otLinkIsCslEnabled(otInstance *aInstance) { return AsCoreType(aInstance).Ge
 
 bool otLinkIsCslSupported(otInstance *aInstance) { return AsCoreType(aInstance).Get<Mac::Mac>().IsCslSupported(); }
 
-uint8_t otLinkCslGetChannel(otInstance *aInstance) { return AsCoreType(aInstance).Get<Mac::Mac>().GetCslChannel(); }
+uint8_t otLinkGetCslChannel(otInstance *aInstance) { return AsCoreType(aInstance).Get<Mac::Mac>().GetCslChannel(); }
 
-otError otLinkCslSetChannel(otInstance *aInstance, uint8_t aChannel)
+otError otLinkSetCslChannel(otInstance *aInstance, uint8_t aChannel)
 {
     Error error = kErrorNone;
 
@@ -409,25 +409,39 @@ exit:
     return error;
 }
 
-uint16_t otLinkCslGetPeriod(otInstance *aInstance) { return AsCoreType(aInstance).Get<Mac::Mac>().GetCslPeriod(); }
-
-otError otLinkCslSetPeriod(otInstance *aInstance, uint16_t aPeriod)
+uint32_t otLinkGetCslPeriod(otInstance *aInstance)
 {
-    Error error = kErrorNone;
+    return Mac::Mac::CslPeriodToUsec(AsCoreType(aInstance).Get<Mac::Mac>().GetCslPeriod());
+}
 
-    VerifyOrExit((aPeriod == 0 || kMinCslPeriod <= aPeriod), error = kErrorInvalidArgs);
-    AsCoreType(aInstance).Get<Mac::Mac>().SetCslPeriod(aPeriod);
+otError otLinkSetCslPeriod(otInstance *aInstance, uint32_t aPeriod)
+{
+    Error    error = kErrorNone;
+    uint16_t periodInTenSymbolsUnit;
+
+    if (aPeriod == 0)
+    {
+        periodInTenSymbolsUnit = 0;
+    }
+    else
+    {
+        VerifyOrExit((aPeriod % kUsPerTenSymbols) == 0, error = kErrorInvalidArgs);
+        periodInTenSymbolsUnit = ClampToUint16(aPeriod / kUsPerTenSymbols);
+        VerifyOrExit(periodInTenSymbolsUnit >= kMinCslPeriod, error = kErrorInvalidArgs);
+    }
+
+    AsCoreType(aInstance).Get<Mac::Mac>().SetCslPeriod(periodInTenSymbolsUnit);
 
 exit:
     return error;
 }
 
-uint32_t otLinkCslGetTimeout(otInstance *aInstance)
+uint32_t otLinkGetCslTimeout(otInstance *aInstance)
 {
     return AsCoreType(aInstance).Get<Mle::MleRouter>().GetCslTimeout();
 }
 
-otError otLinkCslSetTimeout(otInstance *aInstance, uint32_t aTimeout)
+otError otLinkSetCslTimeout(otInstance *aInstance, uint32_t aTimeout)
 {
     Error error = kErrorNone;
 
diff --git a/src/core/common/time.hpp b/src/core/common/time.hpp
index 89c22c239..e1e564161 100644
--- a/src/core/common/time.hpp
+++ b/src/core/common/time.hpp
@@ -65,6 +65,7 @@ public:
     static constexpr uint32_t kOneMinuteInMsec = kOneSecondInMsec * 60; ///< One minute interval in msec.
     static constexpr uint32_t kOneHourInMsec   = kOneMinuteInMsec * 60; ///< One hour interval in msec.
     static constexpr uint32_t kOneDayInMsec    = kOneHourInMsec * 24;   ///< One day interval in msec.
+    static constexpr uint32_t kOneMsecInUsec   = 1000u;                 ///< One millisecond in microseconds.
 
     /**
      * This constant defines a maximum time duration ensured to be longer than any other duration.
diff --git a/src/core/mac/data_poll_sender.cpp b/src/core/mac/data_poll_sender.cpp
index 4f1aaead6..e11f1c82b 100644
--- a/src/core/mac/data_poll_sender.cpp
+++ b/src/core/mac/data_poll_sender.cpp
@@ -504,9 +504,9 @@ uint32_t DataPollSender::CalculatePollPeriod(void) const
         period = Min(period, kRetxPollPeriod);
 
 #if OPENTHREAD_CONFIG_MAC_CSL_RECEIVER_ENABLE
-        if (Get<Mac::Mac>().GetCslPeriodMs() > 0)
+        if (Get<Mac::Mac>().GetCslPeriodInMsec() > 0)
         {
-            period = Min(period, Get<Mac::Mac>().GetCslPeriodMs());
+            period = Min(period, Get<Mac::Mac>().GetCslPeriodInMsec());
         }
 #endif
     }
diff --git a/src/core/mac/mac.cpp b/src/core/mac/mac.cpp
index 4131b2754..f0c3951c7 100644
--- a/src/core/mac/mac.cpp
+++ b/src/core/mac/mac.cpp
@@ -2291,6 +2291,16 @@ void Mac::SetCslPeriod(uint16_t aPeriod)
     UpdateCsl();
 }
 
+uint32_t Mac::GetCslPeriodInMsec(void) const
+{
+    return DivideAndRoundToClosest<uint32_t>(CslPeriodToUsec(GetCslPeriod()), 1000u);
+}
+
+uint32_t Mac::CslPeriodToUsec(uint16_t aPeriodInTenSymbols)
+{
+    return static_cast<uint32_t>(aPeriodInTenSymbols) * kUsPerTenSymbols;
+}
+
 bool Mac::IsCslEnabled(void) const { return !Get<Mle::Mle>().IsRxOnWhenIdle() && IsCslCapable(); }
 
 bool Mac::IsCslCapable(void) const { return (GetCslPeriod() > 0) && IsCslSupported(); }
diff --git a/src/core/mac/mac.hpp b/src/core/mac/mac.hpp
index 26c9320eb..8e218553f 100644
--- a/src/core/mac/mac.hpp
+++ b/src/core/mac/mac.hpp
@@ -620,12 +620,15 @@ public:
     uint16_t GetCslPeriod(void) const { return mCslPeriod; }
 
     /**
-     * Gets the CSL period.
+     * Gets the CSL period in milliseconds.
+     *
+     * If the CSL period cannot be represented exactly in milliseconds, return the rounded value to the nearest
+     * millisecond.
      *
      * @returns CSL period in milliseconds.
      *
      */
-    uint32_t GetCslPeriodMs(void) const { return mCslPeriod * kUsPerTenSymbols / 1000; }
+    uint32_t GetCslPeriodInMsec(void) const;
 
     /**
      * Sets the CSL period.
@@ -635,6 +638,16 @@ public:
      */
     void SetCslPeriod(uint16_t aPeriod);
 
+    /**
+     * This method converts a given CSL period in units of 10 symbols to microseconds.
+     *
+     * @param[in] aPeriodInTenSymbols   The CSL period in unit of 10 symbols.
+     *
+     * @returns The converted CSL period value in microseconds corresponding to @p aPeriodInTenSymbols.
+     *
+     */
+    static uint32_t CslPeriodToUsec(uint16_t aPeriodInTenSymbols);
+
     /**
      * Indicates whether CSL is started at the moment.
      *
@@ -680,7 +693,6 @@ public:
     {
         mLinks.GetSubMac().SetCslParentAccuracy(aCslAccuracy);
     }
-
 #endif // OPENTHREAD_CONFIG_MAC_CSL_RECEIVER_ENABLE
 
 #if OPENTHREAD_CONFIG_MAC_FILTER_ENABLE && OPENTHREAD_CONFIG_RADIO_LINK_IEEE_802_15_4_ENABLE
diff --git a/src/core/mac/sub_mac.hpp b/src/core/mac/sub_mac.hpp
index bbdb88485..7d85683b6 100644
--- a/src/core/mac/sub_mac.hpp
+++ b/src/core/mac/sub_mac.hpp
@@ -395,7 +395,7 @@ public:
     /**
      * Configures CSL parameters in 'SubMac'.
      *
-     * @param[in]  aPeriod    The CSL period.
+     * @param[in]  aPeriod    The CSL period (in unit of 10 symbols).
      * @param[in]  aChannel   The CSL channel.
      * @param[in]  aShortAddr The short source address of CSL receiver's peer.
      * @param[in]  aExtAddr   The extended source address of CSL receiver's peer.
diff --git a/src/core/thread/mle.cpp b/src/core/thread/mle.cpp
index e64483b36..f33cf451c 100644
--- a/src/core/thread/mle.cpp
+++ b/src/core/thread/mle.cpp
@@ -1948,7 +1948,7 @@ void Mle::ScheduleMessageTransmissionTimer(void)
 #if OPENTHREAD_CONFIG_MAC_CSL_RECEIVER_ENABLE
         if (Get<Mac::Mac>().IsCslEnabled())
         {
-            ExitNow(interval = Get<Mac::Mac>().GetCslPeriodMs() + static_cast<uint32_t>(kUnicastRetransmissionDelay));
+            ExitNow(interval = Get<Mac::Mac>().GetCslPeriodInMsec() + kUnicastRetransmissionDelay);
         }
         else
 #endif
diff --git a/src/lib/spinel/spinel.h b/src/lib/spinel/spinel.h
index c251eb1db..ffa370786 100644
--- a/src/lib/spinel/spinel.h
+++ b/src/lib/spinel/spinel.h
@@ -3055,10 +3055,13 @@ enum
     SPINEL_PROP_THREAD_NEW_DATASET = SPINEL_PROP_THREAD_EXT__BEGIN + 40,
 
     /// MAC CSL Period
-    /** Format: `S`
+    /** Format: `L`
      * Required capability: `SPINEL_CAP_THREAD_CSL_RECEIVER`
      *
-     * The CSL period in units of 10 symbols. Value of 0 indicates that CSL should be disabled.
+     * The CSL period in microseconds. Value of 0 indicates that CSL should be disabled.
+     *
+     * The CSL period MUST be a multiple of 160 (which is 802.15 "ten symbols time").
+     *
      */
     SPINEL_PROP_THREAD_CSL_PERIOD = SPINEL_PROP_THREAD_EXT__BEGIN + 41,
 
diff --git a/src/ncp/ncp_base_mtd.cpp b/src/ncp/ncp_base_mtd.cpp
index 78141dbfc..867d3cefd 100644
--- a/src/ncp/ncp_base_mtd.cpp
+++ b/src/ncp/ncp_base_mtd.cpp
@@ -261,12 +261,12 @@ exit:
 #if OPENTHREAD_CONFIG_MAC_CSL_RECEIVER_ENABLE
 template <> otError NcpBase::HandlePropertySet<SPINEL_PROP_THREAD_CSL_PERIOD>(void)
 {
-    uint16_t cslPeriod;
+    uint32_t cslPeriod;
     otError  error = OT_ERROR_NONE;
 
-    SuccessOrExit(error = mDecoder.ReadUint16(cslPeriod));
+    SuccessOrExit(error = mDecoder.ReadUint32(cslPeriod));
 
-    error = otLinkCslSetPeriod(mInstance, cslPeriod);
+    error = otLinkSetCslPeriod(mInstance, cslPeriod);
 
 exit:
     return error;
@@ -274,7 +274,7 @@ exit:
 
 template <> otError NcpBase::HandlePropertyGet<SPINEL_PROP_THREAD_CSL_PERIOD>(void)
 {
-    return mEncoder.WriteUint16(otLinkCslGetPeriod(mInstance));
+    return mEncoder.WriteUint32(otLinkGetCslPeriod(mInstance));
 }
 
 template <> otError NcpBase::HandlePropertySet<SPINEL_PROP_THREAD_CSL_TIMEOUT>(void)
@@ -284,7 +284,7 @@ template <> otError NcpBase::HandlePropertySet<SPINEL_PROP_THREAD_CSL_TIMEOUT>(v
 
     SuccessOrExit(error = mDecoder.ReadUint32(cslTimeout));
 
-    error = otLinkCslSetTimeout(mInstance, cslTimeout);
+    error = otLinkSetCslTimeout(mInstance, cslTimeout);
 
 exit:
     return error;
@@ -292,7 +292,7 @@ exit:
 
 template <> otError NcpBase::HandlePropertyGet<SPINEL_PROP_THREAD_CSL_TIMEOUT>(void)
 {
-    return mEncoder.WriteUint32(otLinkCslGetTimeout(mInstance));
+    return mEncoder.WriteUint32(otLinkGetCslTimeout(mInstance));
 }
 
 template <> otError NcpBase::HandlePropertySet<SPINEL_PROP_THREAD_CSL_CHANNEL>(void)
@@ -302,7 +302,7 @@ template <> otError NcpBase::HandlePropertySet<SPINEL_PROP_THREAD_CSL_CHANNEL>(v
 
     SuccessOrExit(error = mDecoder.ReadUint8(cslChannel));
 
-    error = otLinkCslSetChannel(mInstance, cslChannel);
+    error = otLinkSetCslChannel(mInstance, cslChannel);
 
 exit:
     return error;
@@ -310,7 +310,7 @@ exit:
 
 template <> otError NcpBase::HandlePropertyGet<SPINEL_PROP_THREAD_CSL_CHANNEL>(void)
 {
-    return mEncoder.WriteUint8(otLinkCslGetChannel(mInstance));
+    return mEncoder.WriteUint8(otLinkGetCslChannel(mInstance));
 }
 #endif // OPENTHREAD_CONFIG_MAC_CSL_RECEIVER_ENABLE
 
diff --git a/tests/scripts/expect/cli-discover.exp b/tests/scripts/expect/cli-discover.exp
index 6c769f735..420ba93b3 100755
--- a/tests/scripts/expect/cli-discover.exp
+++ b/tests/scripts/expect/cli-discover.exp
@@ -101,7 +101,7 @@ for {set i 3} {$i <= 4} {incr i} {
 if {$::env(THREAD_VERSION) != "1.1" && $::env(OT_NODE_TYPE) == "cli"} {
     send "csl channel 12\n"
     expect_line "Done"
-    send "csl period 3125\n"
+    send "csl period 500000\n"
     expect_line "Done"
 
     sleep 1
diff --git a/tests/scripts/thread-cert/pktverify/consts.py b/tests/scripts/thread-cert/pktverify/consts.py
index 7bf3c6ae1..69b245a58 100644
--- a/tests/scripts/thread-cert/pktverify/consts.py
+++ b/tests/scripts/thread-cert/pktverify/consts.py
@@ -383,8 +383,8 @@ MAC_FRAME_TYPE_ACK = 0x2
 MAC_FRAME_TYPE_MAC_CMD = 0x3
 
 # CSL
-CSL_DEFAULT_PERIOD = 3125  # 0.5s, 3125 in units of ten symbols
 CSL_DEFAULT_PERIOD_IN_SECOND = 0.5
+CSL_DEFAULT_PERIOD = CSL_DEFAULT_PERIOD_IN_SECOND * 1000 * 1000  # in usec
 US_PER_TEN_SYMBOLS = 160
 CSL_IE_ID = 0x1a
 CSL_DEFAULT_TIMEOUT = 30
diff --git a/tests/scripts/thread-cert/v1_2_test_single_probe.py b/tests/scripts/thread-cert/v1_2_test_single_probe.py
index 93a8f67fe..5b29aaac8 100755
--- a/tests/scripts/thread-cert/v1_2_test_single_probe.py
+++ b/tests/scripts/thread-cert/v1_2_test_single_probe.py
@@ -36,7 +36,7 @@ import config
 LEADER = 1
 SSED_1 = 2
 
-CSL_PERIOD = 500 * 6.25  # 500ms
+CSL_PERIOD = 500 * 1000  # 0.5 in usec
 CSL_TIMEOUT = 30  # 30s
 
 
diff --git a/tools/harness-thci/OpenThread.py b/tools/harness-thci/OpenThread.py
index 7bff870fa..47e83479e 100644
--- a/tools/harness-thci/OpenThread.py
+++ b/tools/harness-thci/OpenThread.py
@@ -2923,11 +2923,8 @@ class OpenThreadTHCI(object):
         Args:
             period: csl period in ms
 
-        note: OT command 'csl period' accepts parameter in unit of 10 symbols,
-        period is converted from unit ms to ten symbols (160us per 10 symbols).
-
         """
-        cmd = 'csl period %u' % (period * 6.25)
+        cmd = 'csl period %u' % (period * 1000)
         return self.__executeCommand(cmd)[-1] == 'Done'
 
     @staticmethod
diff --git a/tools/otci/otci/otci.py b/tools/otci/otci/otci.py
index 7df5930fd..e60acf8ee 100644
--- a/tools/otci/otci/otci.py
+++ b/tools/otci/otci/otci.py
@@ -1369,7 +1369,7 @@ class OTCI(object):
     # TODO: csl period <period>
     # TODO: csl timeout <timeout>
 
-    _CSL_PERIOD_PATTERN = re.compile(r'(\d+)\(in units of 10 symbols\), \d+ms')
+    _CSL_PERIOD_PATTERN = re.compile(r'(\d+)us')
     _CSL_TIMEOUT_PATTERN = re.compile(r'(\d+)s')
 
     def get_csl_config(self) -> Dict[str, int]:
@@ -1398,7 +1398,7 @@ class OTCI(object):
         """Configure CSL parameters.
 
         :param channel: Set CSL channel.
-        :param period: Set CSL period in units of 10 symbols. Disable CSL by setting this parameter to 0.
+        :param period: Set CSL period in usec. Disable CSL by setting this parameter to 0.
         :param timeout: Set the CSL timeout in seconds.
         """
 
diff --git a/tools/otci/tests/test_otci.py b/tools/otci/tests/test_otci.py
index 736647069..8e5a598c5 100644
--- a/tools/otci/tests/test_otci.py
+++ b/tools/otci/tests/test_otci.py
@@ -252,7 +252,7 @@ class TestOTCI(unittest.TestCase):
             self.assertTrue(all(x == 0 for name, x in leader.get_counter(counter_name).items() if "Time" not in name))
 
         logging.info("CSL config: %r", leader.get_csl_config())
-        leader.config_csl(channel=13, period=100, timeout=200)
+        leader.config_csl(channel=13, period=16000, timeout=200)
         logging.info("CSL config: %r", leader.get_csl_config())
 
         logging.info("EID-to-RLOC cache: %r", leader.get_eidcache())