diff --git a/internal/json/json_test.go b/internal/json/json_test.go
new file mode 100644
index 000000000..7ff8b7341
--- /dev/null
+++ b/internal/json/json_test.go
@@ -0,0 +1,93 @@
+// Copyright GoFrame Author(https://goframe.org). All Rights Reserved.
+//
+// This Source Code Form is subject to the terms of the MIT License.
+// If a copy of the MIT was not distributed with this file,
+// You can obtain one at https://github.com/gogf/gf.
+
+package json_test
+
+import (
+	"github.com/gogf/gf/frame/g"
+	"github.com/gogf/gf/internal/json"
+	"github.com/gogf/gf/test/gtest"
+	"testing"
+)
+
+type User struct {
+	Id   int64  `json:"id"`
+	Name string `json:"name"`
+}
+
+var (
+	user = &User{
+		Id:   1265476890672672808,
+		Name: "john",
+	}
+	userBytes, _ = json.Marshal(user)
+)
+
+func TestMarshal(t *testing.T) {
+	gtest.C(t, func(t *gtest.T) {
+		b, err := json.Marshal(user)
+		t.AssertNil(err)
+		t.Assert(b, `{"id":1265476890672672808,"name":"john"}`)
+	})
+}
+
+func TestMarshalIndent(t *testing.T) {
+	gtest.C(t, func(t *gtest.T) {
+		b, err := json.MarshalIndent(user, "#", "@")
+		t.AssertNil(err)
+		t.Assert(b, `{
+#@"id": 1265476890672672808,
+#@"name": "john"
+#}`)
+	})
+}
+
+func TestUnmarshal(t *testing.T) {
+	gtest.C(t, func(t *gtest.T) {
+		var m map[string]interface{}
+		b, _ := json.Marshal(g.Map{
+			"user": user,
+		})
+		err := json.Unmarshal(b, &m)
+		t.AssertNil(err)
+		// precision lost for big int.
+		t.Assert(m["user"], g.Map{
+			"id":   1265476890672672800,
+			"name": user.Name,
+		})
+	})
+}
+
+func TestUnmarshalUseNumber(t *testing.T) {
+	gtest.C(t, func(t *gtest.T) {
+		var m map[string]interface{}
+		b, _ := json.Marshal(g.Map{
+			"user": user,
+		})
+		err := json.UnmarshalUseNumber(b, &m)
+		t.AssertNil(err)
+		t.Assert(m["user"], g.Map{
+			"id":   user.Id,
+			"name": user.Name,
+		})
+	})
+}
+
+func TestValid(t *testing.T) {
+	gtest.C(t, func(t *gtest.T) {
+		m := g.Map{
+			`{}`:                     true,
+			`{"id":1,"name":"john"}`: true,
+			`1`:                      true,
+			`"john"`:                 true,
+			`"`:                      false,
+			`<xml></xml>`:            false,
+		}
+		for k, v := range m {
+			t.Assert(json.Valid([]byte(k)), v)
+		}
+	})
+}