diff --git a/src/core/coap/coap_header.cpp b/src/core/coap/coap_header.cpp
index e0e2e4a77..052efcfe3 100644
--- a/src/core/coap/coap_header.cpp
+++ b/src/core/coap/coap_header.cpp
@@ -282,10 +282,10 @@ otError Header::AppendObserveOption(uint32_t aObserve)
 
 otError Header::AppendUriPathOptions(const char *aUriPath)
 {
-    otError        error = OT_ERROR_NONE;
-    const char *   cur   = aUriPath;
-    const char *   end;
-    Header::Option coapOption;
+    otError     error = OT_ERROR_NONE;
+    const char *cur   = aUriPath;
+    const char *end;
+    Option      coapOption;
 
     coapOption.mNumber = OT_COAP_OPTION_URI_PATH;
 
@@ -397,7 +397,7 @@ const Header::Option *Header::GetNextOption(void)
     mOption.mLength = optionLength;
     mOption.mValue  = mHeader.mBytes + mNextOptionOffset;
     mNextOptionOffset += optionLength;
-    rval = static_cast<Header::Option *>(&mOption);
+    rval = static_cast<Option *>(&mOption);
 
 exit:
     return rval;
diff --git a/src/core/coap/coap_header.hpp b/src/core/coap/coap_header.hpp
index d61017080..d5a067e1d 100644
--- a/src/core/coap/coap_header.hpp
+++ b/src/core/coap/coap_header.hpp
@@ -145,7 +145,7 @@ public:
      * @returns The Type value.
      *
      */
-    Type GetType(void) const { return static_cast<Header::Type>(mHeader.mFields.mVersionTypeToken & kTypeMask); }
+    Type GetType(void) const { return static_cast<Type>(mHeader.mFields.mVersionTypeToken & kTypeMask); }
 
     /**
      * This method sets the Type value.