diff --git a/core/mapping/unmarshaler.go b/core/mapping/unmarshaler.go
index b7285057d..1ec535d1f 100644
--- a/core/mapping/unmarshaler.go
+++ b/core/mapping/unmarshaler.go
@@ -752,7 +752,7 @@ func (u *Unmarshaler) processNamedFieldWithValueFromString(fieldType reflect.Typ
 		switch mt := mapValue.(type) {
 		case string:
 			checkValue = mt
-		case json.Number:
+		case fmt.Stringer:
 			checkValue = mt.String()
 		default:
 			return fmt.Errorf("the value in map is not string or json.Number, but %s",
diff --git a/core/mapping/unmarshaler_test.go b/core/mapping/unmarshaler_test.go
index 83229fd4d..99a0984d8 100644
--- a/core/mapping/unmarshaler_test.go
+++ b/core/mapping/unmarshaler_test.go
@@ -260,7 +260,7 @@ func TestUnmarshalIntWithString(t *testing.T) {
 		}
 
 		var in inner
-		assert.Nil(t, UnmarshalKey(m, &in))
+		assert.NoError(t, UnmarshalKey(m, &in))
 		assert.Equal(t, int64(0), in.Int)
 	})
 
@@ -273,9 +273,37 @@ func TestUnmarshalIntWithString(t *testing.T) {
 		}
 
 		var in inner
-		assert.Nil(t, UnmarshalKey(m, &in))
+		assert.NoError(t, UnmarshalKey(m, &in))
 		assert.Equal(t, int64(0), in.Int)
 	})
+
+	t.Run("int with options", func(t *testing.T) {
+		type inner struct {
+			Int int64 `key:"int,string,options=[0,1]"`
+		}
+		m := map[string]interface{}{
+			"int": nil,
+		}
+
+		var in inner
+		assert.Error(t, UnmarshalKey(m, &in))
+	})
+
+	t.Run("int with options", func(t *testing.T) {
+		type (
+			StrType string
+
+			inner struct {
+				Int int64 `key:"int,string,options=[0,1]"`
+			}
+		)
+		m := map[string]interface{}{
+			"int": StrType("0"),
+		}
+
+		var in inner
+		assert.Error(t, UnmarshalKey(m, &in))
+	})
 }
 
 func TestUnmarshalBoolSliceRequired(t *testing.T) {