diff --git a/src/core/coap/coap.cpp b/src/core/coap/coap.cpp
index 6c5328aec..346d164a6 100644
--- a/src/core/coap/coap.cpp
+++ b/src/core/coap/coap.cpp
@@ -640,6 +640,8 @@ Error CoapBase::PrepareNextBlockRequest(Message::BlockType aType,
     blockOption = (aType == Message::kBlockType1) ? kOptionBlock1 : kOptionBlock2;
 
     aRequest.Init(kTypeConfirmable, static_cast<ot::Coap::Code>(aRequestOld.GetCode()));
+    // Per RFC 7959, all requests in a block-wise transfer MUST use the same token.
+    IgnoreError(aRequest.SetTokenFromMessage(aRequestOld));
     SuccessOrExit(error = iterator.Init(aRequestOld));
 
     // Copy options from last response to next message