diff --git a/src/cli/cli_uart.hpp b/src/cli/cli_uart.hpp
index c7e06c919..7f0f79cd6 100644
--- a/src/cli/cli_uart.hpp
+++ b/src/cli/cli_uart.hpp
@@ -111,9 +111,9 @@ public:
 private:
     enum
     {
-        kRxBufferSize = 512,
-        kTxBufferSize = 1024,
-        kMaxLineLength = 128,
+        kRxBufferSize = OPENTHREAD_CONFIG_CLI_UART_RX_BUFFER_SIZE,
+        kTxBufferSize = OPENTHREAD_CONFIG_CLI_UART_TX_BUFFER_SIZE,
+        kMaxLineLength = OPENTHREAD_CONFIG_CLI_MAX_LINE_LENGTH,
     };
 
     otError ProcessCommand(void);
diff --git a/src/core/openthread-core-default-config.h b/src/core/openthread-core-default-config.h
index 37e83fcf0..8e5f4d75f 100644
--- a/src/core/openthread-core-default-config.h
+++ b/src/core/openthread-core-default-config.h
@@ -231,6 +231,36 @@
 #define OPENTHREAD_CONFIG_ADDRESS_QUERY_MAX_RETRY_DELAY         28800
 #endif
 
+/**
+ * @def OPENTHREAD_CONFIG_CLI_MAX_LINE_LENGTH
+ *
+ *  The maximum size of the CLI line in bytes
+ *
+ */
+#ifndef OPENTHREAD_CONFIG_CLI_MAX_LINE_LENGTH
+#define OPENTHREAD_CONFIG_CLI_MAX_LINE_LENGTH                   128
+#endif
+
+/**
+ * @def OPENTHREAD_CONFIG_CLI_UART_RX_BUFFER_SIZE
+ *
+ *  The size of CLI UART RX buffer in bytes
+ *
+ */
+#ifndef OPENTHREAD_CONFIG_CLI_UART_RX_BUFFER_SIZE
+#define OPENTHREAD_CONFIG_CLI_UART_RX_BUFFER_SIZE               512
+#endif
+
+/**
+ * @def OPENTHREAD_CONFIG_CLI_TX_BUFFER_SIZE
+ *
+ *  The size of CLI message buffer in bytes
+ *
+ */
+#ifndef OPENTHREAD_CONFIG_CLI_UART_TX_BUFFER_SIZE
+#define OPENTHREAD_CONFIG_CLI_UART_TX_BUFFER_SIZE               1024
+#endif
+
 /**
  * @def OPENTHREAD_CONFIG_MAX_CHILDREN
  *