diff --git a/constant/adapters.go b/constant/adapters.go
index 30ea50124..4593fed04 100644
--- a/constant/adapters.go
+++ b/constant/adapters.go
@@ -103,6 +103,6 @@ func (at AdapterType) String() string {
 	case LoadBalance:
 		return "LoadBalance"
 	default:
-		return "Unknow"
+		return "Unknown"
 	}
 }
diff --git a/constant/rule.go b/constant/rule.go
index fa8a12c79..40756264b 100644
--- a/constant/rule.go
+++ b/constant/rule.go
@@ -36,7 +36,7 @@ func (rt RuleType) String() string {
 	case MATCH:
 		return "MATCH"
 	default:
-		return "Unknow"
+		return "Unknown"
 	}
 }