diff --git a/domain/consensus/processes/blockvalidator/proof_of_work.go b/domain/consensus/processes/blockvalidator/proof_of_work.go
index b83076c79..ffb38ba8a 100644
--- a/domain/consensus/processes/blockvalidator/proof_of_work.go
+++ b/domain/consensus/processes/blockvalidator/proof_of_work.go
@@ -97,7 +97,7 @@ func (v *blockValidator) checkProofOfWork(header *externalapi.DomainBlockHeader)
 	if !v.skipPoW {
 		valid := pow.CheckProofOfWorkWithTarget(header, target)
 		if !valid {
-			return errors.Wrap(ruleerrors.ErrUnexpectedDifficulty, "block has invalid difficulty")
+			return errors.Wrap(ruleerrors.ErrInvalidPoW, "block has invalid proof of work")
 		}
 	}
 	return nil
diff --git a/domain/consensus/ruleerrors/rule_error.go b/domain/consensus/ruleerrors/rule_error.go
index 6d6c0fe97..4cd5e99d5 100644
--- a/domain/consensus/ruleerrors/rule_error.go
+++ b/domain/consensus/ruleerrors/rule_error.go
@@ -44,6 +44,9 @@ var (
 	// range.
 	ErrUnexpectedDifficulty = newRuleError("ErrUnexpectedDifficulty")
 
+	// ErrInvalidPoW indicates that the block proof-of-work is invalid.
+	ErrInvalidPoW = newRuleError("ErrInvalidPoW")
+
 	// ErrHighHash indicates the block does not hash to a value which is
 	// lower than the required target difficultly.
 	ErrHighHash = newRuleError("ErrHighHash")
@@ -56,7 +59,7 @@ var (
 	// the expected value.
 	ErrBadUTXOCommitment = newRuleError("ErrBadUTXOCommitment")
 
-	// ErrInvalidSubnetwork indicates the subnetwork is now allowed.
+	// ErrInvalidSubnetwork indicates the subnetwork is not allowed.
 	ErrInvalidSubnetwork = newRuleError("ErrInvalidSubnetwork")
 
 	// ErrFinalityPointTimeTooOld indicates a block has a timestamp before the