diff --git a/src/core/thread/mesh_forwarder.cpp b/src/core/thread/mesh_forwarder.cpp
index 364b155a0..e2624fe71 100644
--- a/src/core/thread/mesh_forwarder.cpp
+++ b/src/core/thread/mesh_forwarder.cpp
@@ -1201,6 +1201,27 @@ void MeshForwarder::ClearReassemblyList(void)
     }
 }
 
+Error MeshForwarder::RemoveUnsecureReassemblyMessage(EvictReason aEvictReason)
+{
+    Error error = kErrorNotFound;
+
+    VerifyOrExit(aEvictReason == kEvictReasonNoMessageBuffer);
+
+    for (Message &message : mReassemblyList)
+    {
+        if (!message.IsLinkSecurityEnabled())
+        {
+            LogMessage(kMessageReassemblyDrop, message, kErrorNoBufs);
+            mCounters.UpdateOnDrop(message);
+            mReassemblyList.DequeueAndFree(message);
+            ExitNow(error = kErrorNone);
+        }
+    }
+
+exit:
+    return error;
+}
+
 void MeshForwarder::HandleTimeTick(void)
 {
     bool continueRxingTicks = false;
diff --git a/src/core/thread/mesh_forwarder.hpp b/src/core/thread/mesh_forwarder.hpp
index 70db267ac..c89107865 100644
--- a/src/core/thread/mesh_forwarder.hpp
+++ b/src/core/thread/mesh_forwarder.hpp
@@ -453,6 +453,7 @@ private:
                                  Message::Priority       aPriority);
     Error HandleDatagram(Message &aMessage, const Mac::Address &aMacSource);
     void  ClearReassemblyList(void);
+    Error RemoveUnsecureReassemblyMessage(EvictReason aEvictReason);
     void  HandleDiscoverComplete(void);
 
     void          HandleReceivedFrame(Mac::RxFrame &aFrame);
diff --git a/src/core/thread/mesh_forwarder_ftd.cpp b/src/core/thread/mesh_forwarder_ftd.cpp
index c2c273717..f69096f47 100644
--- a/src/core/thread/mesh_forwarder_ftd.cpp
+++ b/src/core/thread/mesh_forwarder_ftd.cpp
@@ -180,6 +180,9 @@ Error MeshForwarder::EvictMessage(Message::Priority aPriority, EvictReason aEvic
     Error    error = kErrorNotFound;
     Message *evict = nullptr;
 
+    error = RemoveUnsecureReassemblyMessage(aEvictReason);
+    VerifyOrExit(error == kErrorNotFound);
+
 #if OPENTHREAD_CONFIG_DELAY_AWARE_QUEUE_MANAGEMENT_ENABLE
     error = RemoveAgedMessages();
     VerifyOrExit(error == kErrorNotFound);
diff --git a/src/core/thread/mesh_forwarder_mtd.cpp b/src/core/thread/mesh_forwarder_mtd.cpp
index df47e56a7..7fdbbbe55 100644
--- a/src/core/thread/mesh_forwarder_mtd.cpp
+++ b/src/core/thread/mesh_forwarder_mtd.cpp
@@ -56,11 +56,12 @@ void MeshForwarder::SendMessage(OwnedPtr<Message> aMessagePtr)
 
 Error MeshForwarder::EvictMessage(Message::Priority aPriority, EvictReason aEvictReason)
 {
-    OT_UNUSED_VARIABLE(aEvictReason);
-
     Error    error = kErrorNotFound;
     Message *message;
 
+    error = RemoveUnsecureReassemblyMessage(aEvictReason);
+    VerifyOrExit(error == kErrorNotFound);
+
 #if OPENTHREAD_CONFIG_DELAY_AWARE_QUEUE_MANAGEMENT_ENABLE
     error = RemoveAgedMessages();
     VerifyOrExit(error == kErrorNotFound);