diff --git a/src/core/mac/mac.cpp b/src/core/mac/mac.cpp
index f12f56606..5ae6e0957 100644
--- a/src/core/mac/mac.cpp
+++ b/src/core/mac/mac.cpp
@@ -671,6 +671,7 @@ void Mac::ProcessTransmitSecurity(Frame &aFrame)
     case Frame::kKeyIdMode0:
         key = mKeyManager.GetKek();
         frameCounter = mKeyManager.GetKekFrameCounter();
+        mKeyManager.IncrementKekFrameCounter();
         extAddress = &mExtAddress;
         break;