diff --git a/core/block_validator.go b/core/block_validator.go
index e710d7469a..a54a4eaaad 100644
--- a/core/block_validator.go
+++ b/core/block_validator.go
@@ -108,8 +108,10 @@ func (v *BlockValidator) ValidateBody(block *types.Block) error {
 			return nil
 		},
 		func() error {
-			if v.remoteValidator != nil && !v.remoteValidator.AncestorVerified(block.Header()) {
-				return fmt.Errorf("%w, number: %s, hash: %s", ErrAncestorHasNotBeenVerified, block.Number(), block.Hash())
+			if v.remoteValidator != nil {
+				if verified, err := v.remoteValidator.AncestorVerified(block.Header()); !verified {
+					return fmt.Errorf("%w, number: %s, hash: %s, error: %s", ErrAncestorHasNotBeenVerified, block.Number(), block.Hash(), err.Error())
+				}
 			}
 			return nil
 		},
diff --git a/core/remote_state_verifier.go b/core/remote_state_verifier.go
index bf43f6de81..8d0c4dade5 100644
--- a/core/remote_state_verifier.go
+++ b/core/remote_state_verifier.go
@@ -169,7 +169,7 @@ func (vm *remoteVerifyManager) NewBlockVerifyTask(header *types.Header) {
 			}
 
 			if header.TxHash == types.EmptyRootHash {
-				log.Debug("this is an empty block:", "block", hash, "number", header.Number)
+				log.Info("this is an empty block:", "block", hash, "number", header.Number)
 				vm.cacheBlockVerified(hash)
 				return
 			}
@@ -208,13 +208,13 @@ func (vm *remoteVerifyManager) cacheBlockVerified(hash common.Hash) {
 }
 
 // AncestorVerified function check block has been verified or it's a empty block.
-func (vm *remoteVerifyManager) AncestorVerified(header *types.Header) bool {
+func (vm *remoteVerifyManager) AncestorVerified(header *types.Header) (bool, error) {
 	// find header of H-11 block.
 	header = vm.bc.GetHeaderByNumber(header.Number.Uint64() - maxForkHeight)
 	// If start from genesis block, there has not a H-11 block,return true.
 	// Either if the block is an empty block, return true.
 	if header == nil || header.TxHash == types.EmptyRootHash {
-		return true
+		return true, nil
 	}
 
 	hash := header.Hash()
@@ -229,12 +229,15 @@ func (vm *remoteVerifyManager) AncestorVerified(header *types.Header) bool {
 		select {
 		case <-task.terminalCh:
 		case <-timeout.C:
-			return false
+			return false, fmt.Errorf("task of %s is timeout", hash.String())
 		}
 	}
 
 	_, exist = vm.verifiedCache.Get(hash)
-	return exist
+	if !exist {
+		return  false, fmt.Errorf("block of %s has not been marked as verified", hash.String())
+	}
+	return true, nil
 }
 
 func (vm *remoteVerifyManager) HandleRootResponse(vr *VerifyResult, pid string) error {