diff --git a/include/openthread/coap.h b/include/openthread/coap.h
index 4cfed8d8d..b7ccfef52 100644
--- a/include/openthread/coap.h
+++ b/include/openthread/coap.h
@@ -328,7 +328,7 @@ otError otCoapHeaderAppendUintOption(otCoapHeader *aHeader, uint16_t aNumber, ui
 otError otCoapHeaderAppendObserveOption(otCoapHeader *aHeader, uint32_t aObserve);
 
 /**
- * This function appends an Uri-Path option.
+ * This function appends a Uri-Path option.
  *
  * @param[inout]  aHeader   A pointer to the CoAP header.
  * @param[in]     aUriPath  A pointer to a NULL-terminated string.
@@ -340,6 +340,19 @@ otError otCoapHeaderAppendObserveOption(otCoapHeader *aHeader, uint32_t aObserve
  */
 otError otCoapHeaderAppendUriPathOptions(otCoapHeader *aHeader, const char *aUriPath);
 
+/**
+ * This function appends a Proxy-Uri option.
+ *
+ * @param[inout]  aHeader   A pointer to the CoAP header.
+ * @param[in]     aUriPath  A pointer to a NULL-terminated string.
+ *
+ * @retval OT_ERROR_NONE          Successfully appended the option.
+ * @retval OT_ERROR_INVALID_ARGS  The option type is not equal or greater than the last option type.
+ * @retval OT_ERROR_NO_BUFS       The option length exceeds the buffer size.
+ *
+ */
+otError otCoapHeaderAppendProxyUriOption(otCoapHeader *aHeader, const char *aUriPath);
+
 /**
  * This function appends a Max-Age option.
  *
diff --git a/src/core/api/coap_api.cpp b/src/core/api/coap_api.cpp
index b2c30bb54..1573181c9 100644
--- a/src/core/api/coap_api.cpp
+++ b/src/core/api/coap_api.cpp
@@ -83,6 +83,11 @@ otError otCoapHeaderAppendUriPathOptions(otCoapHeader *aHeader, const char *aUri
     return static_cast<Coap::Header *>(aHeader)->AppendUriPathOptions(aUriPath);
 }
 
+otError otCoapHeaderAppendProxyUriOption(otCoapHeader *aHeader, const char *aUriPath)
+{
+    return static_cast<Coap::Header *>(aHeader)->AppendProxyUriOption(aUriPath);
+}
+
 otError otCoapHeaderAppendMaxAgeOption(otCoapHeader *aHeader, uint32_t aMaxAge)
 {
     return static_cast<Coap::Header *>(aHeader)->AppendMaxAgeOption(aMaxAge);
diff --git a/src/core/coap/coap_header.cpp b/src/core/coap/coap_header.cpp
index 7c86d4889..4114480ae 100644
--- a/src/core/coap/coap_header.cpp
+++ b/src/core/coap/coap_header.cpp
@@ -275,6 +275,17 @@ otError Header::AppendUintOption(uint16_t aNumber, uint32_t aValue)
     return AppendOption(coapOption);
 }
 
+otError Header::AppendStringOption(uint16_t aNumber, const char *aValue)
+{
+    Option coapOption;
+
+    coapOption.mNumber = aNumber;
+    coapOption.mLength = static_cast<uint16_t>(strlen(aValue));
+    coapOption.mValue  = reinterpret_cast<const uint8_t *>(aValue);
+
+    return AppendOption(coapOption);
+}
+
 otError Header::AppendObserveOption(uint32_t aObserve)
 {
     return AppendUintOption(OT_COAP_OPTION_OBSERVE, aObserve & 0xFFFFFF);
@@ -297,14 +308,17 @@ otError Header::AppendUriPathOptions(const char *aUriPath)
         cur = end + 1;
     }
 
-    coapOption.mLength = static_cast<uint16_t>(strlen(cur));
-    coapOption.mValue  = reinterpret_cast<const uint8_t *>(cur);
-    SuccessOrExit(error = AppendOption(coapOption));
+    SuccessOrExit(error = AppendStringOption(OT_COAP_OPTION_URI_PATH, cur));
 
 exit:
     return error;
 }
 
+otError Header::AppendProxyUriOption(const char *aProxyUri)
+{
+    return AppendStringOption(OT_COAP_OPTION_PROXY_URI, aProxyUri);
+}
+
 otError Header::AppendContentFormatOption(otCoapOptionContentFormat aContentFormat)
 {
     return AppendUintOption(OT_COAP_OPTION_CONTENT_FORMAT, static_cast<uint32_t>(aContentFormat));
@@ -317,13 +331,7 @@ otError Header::AppendMaxAgeOption(uint32_t aMaxAge)
 
 otError Header::AppendUriQueryOption(const char *aUriQuery)
 {
-    Option coapOption;
-
-    coapOption.mNumber = OT_COAP_OPTION_URI_QUERY;
-    coapOption.mLength = static_cast<uint16_t>(strlen(aUriQuery));
-    coapOption.mValue  = reinterpret_cast<const uint8_t *>(aUriQuery);
-
-    return AppendOption(coapOption);
+    return AppendStringOption(OT_COAP_OPTION_URI_QUERY, aUriQuery);
 }
 
 const Header::Option *Header::GetFirstOption(void)
diff --git a/src/core/coap/coap_header.hpp b/src/core/coap/coap_header.hpp
index cf8e30e38..638ce6ff4 100644
--- a/src/core/coap/coap_header.hpp
+++ b/src/core/coap/coap_header.hpp
@@ -306,6 +306,19 @@ public:
      */
     otError AppendUintOption(uint16_t aNumber, uint32_t aValue);
 
+    /**
+     * This method appends a string CoAP option.
+     *
+     * @param[in]  aNumber  The CoAP Option number.
+     * @param[in]  aValue   The CoAP Option string value.
+     *
+     * @retval OT_ERROR_NONE          Successfully appended the option.
+     * @retval OT_ERROR_INVALID_ARGS  The option type is not equal or greater than the last option type.
+     * @retval OT_ERROR_NO_BUFS       The option length exceeds the buffer size.
+     *
+     */
+    otError AppendStringOption(uint16_t aNumber, const char *aValue);
+
     /**
      * This method appends an Observe option.
      *
@@ -320,7 +333,7 @@ public:
     /**
      * This method appends a Uri-Path option.
      *
-     * @param[in]  aUriPath  A pointer to a NULL-terminated string.
+     * @param[in]  aUriPath           A pointer to a NULL-terminated string.
      *
      * @retval OT_ERROR_NONE          Successfully appended the option.
      * @retval OT_ERROR_INVALID_ARGS  The option type is not equal or greater than the last option type.
@@ -329,6 +342,18 @@ public:
      */
     otError AppendUriPathOptions(const char *aUriPath);
 
+    /**
+     * This method appends a Proxy-Uri option.
+     *
+     * @param[in]  aProxyUri          A pointer to a NULL-terminated string.
+     *
+     * @retval OT_ERROR_NONE          Successfully appended the option.
+     * @retval OT_ERROR_INVALID_ARGS  The option type is not equal or greater than the last option type.
+     * @retval OT_ERROR_NO_BUFS       The option length exceeds the buffer size.
+     *
+     */
+    otError AppendProxyUriOption(const char *aProxyUri);
+
     /**
      * This method appends a Content-Format option.
      *