diff --git a/container/glist/glist.go b/container/glist/glist.go
index d3e82a082..3dab3ee86 100644
--- a/container/glist/glist.go
+++ b/container/glist/glist.go
@@ -507,7 +507,7 @@ func (l *List) String() string {
 }
 
 // MarshalJSON implements the interface MarshalJSON for json.Marshal.
-func (l *List) MarshalJSON() ([]byte, error) {
+func (l List) MarshalJSON() ([]byte, error) {
 	return json.Marshal(l.FrontAll())
 }
 
diff --git a/container/gmap/gmap_hash_any_any_map.go b/container/gmap/gmap_hash_any_any_map.go
index 9b268ae0d..05e451945 100644
--- a/container/gmap/gmap_hash_any_any_map.go
+++ b/container/gmap/gmap_hash_any_any_map.go
@@ -461,7 +461,7 @@ func (m *AnyAnyMap) String() string {
 }
 
 // MarshalJSON implements the interface MarshalJSON for json.Marshal.
-func (m *AnyAnyMap) MarshalJSON() ([]byte, error) {
+func (m AnyAnyMap) MarshalJSON() ([]byte, error) {
 	return json.Marshal(gconv.Map(m.Map()))
 }
 
diff --git a/container/gmap/gmap_hash_int_any_map.go b/container/gmap/gmap_hash_int_any_map.go
index 15a0953e0..a4e509cd4 100644
--- a/container/gmap/gmap_hash_int_any_map.go
+++ b/container/gmap/gmap_hash_int_any_map.go
@@ -460,7 +460,7 @@ func (m *IntAnyMap) String() string {
 }
 
 // MarshalJSON implements the interface MarshalJSON for json.Marshal.
-func (m *IntAnyMap) MarshalJSON() ([]byte, error) {
+func (m IntAnyMap) MarshalJSON() ([]byte, error) {
 	m.mu.RLock()
 	defer m.mu.RUnlock()
 	return json.Marshal(m.data)
diff --git a/container/gmap/gmap_hash_int_int_map.go b/container/gmap/gmap_hash_int_int_map.go
index 36e2f74fb..8fe1fa7f2 100644
--- a/container/gmap/gmap_hash_int_int_map.go
+++ b/container/gmap/gmap_hash_int_int_map.go
@@ -431,7 +431,7 @@ func (m *IntIntMap) String() string {
 }
 
 // MarshalJSON implements the interface MarshalJSON for json.Marshal.
-func (m *IntIntMap) MarshalJSON() ([]byte, error) {
+func (m IntIntMap) MarshalJSON() ([]byte, error) {
 	m.mu.RLock()
 	defer m.mu.RUnlock()
 	return json.Marshal(m.data)
diff --git a/container/gmap/gmap_hash_int_str_map.go b/container/gmap/gmap_hash_int_str_map.go
index 94a026ef8..27697bc44 100644
--- a/container/gmap/gmap_hash_int_str_map.go
+++ b/container/gmap/gmap_hash_int_str_map.go
@@ -431,7 +431,7 @@ func (m *IntStrMap) String() string {
 }
 
 // MarshalJSON implements the interface MarshalJSON for json.Marshal.
-func (m *IntStrMap) MarshalJSON() ([]byte, error) {
+func (m IntStrMap) MarshalJSON() ([]byte, error) {
 	m.mu.RLock()
 	defer m.mu.RUnlock()
 	return json.Marshal(m.data)
diff --git a/container/gmap/gmap_hash_str_any_map.go b/container/gmap/gmap_hash_str_any_map.go
index 8846a2971..27708b230 100644
--- a/container/gmap/gmap_hash_str_any_map.go
+++ b/container/gmap/gmap_hash_str_any_map.go
@@ -456,7 +456,7 @@ func (m *StrAnyMap) String() string {
 }
 
 // MarshalJSON implements the interface MarshalJSON for json.Marshal.
-func (m *StrAnyMap) MarshalJSON() ([]byte, error) {
+func (m StrAnyMap) MarshalJSON() ([]byte, error) {
 	m.mu.RLock()
 	defer m.mu.RUnlock()
 	return json.Marshal(m.data)
diff --git a/container/gmap/gmap_hash_str_int_map.go b/container/gmap/gmap_hash_str_int_map.go
index a6c7fc773..2041473b7 100644
--- a/container/gmap/gmap_hash_str_int_map.go
+++ b/container/gmap/gmap_hash_str_int_map.go
@@ -435,7 +435,7 @@ func (m *StrIntMap) String() string {
 }
 
 // MarshalJSON implements the interface MarshalJSON for json.Marshal.
-func (m *StrIntMap) MarshalJSON() ([]byte, error) {
+func (m StrIntMap) MarshalJSON() ([]byte, error) {
 	m.mu.RLock()
 	defer m.mu.RUnlock()
 	return json.Marshal(m.data)
diff --git a/container/gmap/gmap_hash_str_str_map.go b/container/gmap/gmap_hash_str_str_map.go
index 1ffb2b527..d2c8a0bd1 100644
--- a/container/gmap/gmap_hash_str_str_map.go
+++ b/container/gmap/gmap_hash_str_str_map.go
@@ -434,7 +434,7 @@ func (m *StrStrMap) String() string {
 }
 
 // MarshalJSON implements the interface MarshalJSON for json.Marshal.
-func (m *StrStrMap) MarshalJSON() ([]byte, error) {
+func (m StrStrMap) MarshalJSON() ([]byte, error) {
 	m.mu.RLock()
 	defer m.mu.RUnlock()
 	return json.Marshal(m.data)
diff --git a/container/gmap/gmap_list_map.go b/container/gmap/gmap_list_map.go
index 3ef696dfe..eed95f1a6 100644
--- a/container/gmap/gmap_list_map.go
+++ b/container/gmap/gmap_list_map.go
@@ -514,7 +514,7 @@ func (m *ListMap) String() string {
 }
 
 // MarshalJSON implements the interface MarshalJSON for json.Marshal.
-func (m *ListMap) MarshalJSON() ([]byte, error) {
+func (m ListMap) MarshalJSON() ([]byte, error) {
 	return json.Marshal(gconv.Map(m.Map()))
 }
 
diff --git a/container/gset/gset_any_set.go b/container/gset/gset_any_set.go
index 9ab7da1ad..b04b05667 100644
--- a/container/gset/gset_any_set.go
+++ b/container/gset/gset_any_set.go
@@ -467,7 +467,7 @@ func (set *Set) Walk(f func(item interface{}) interface{}) *Set {
 }
 
 // MarshalJSON implements the interface MarshalJSON for json.Marshal.
-func (set *Set) MarshalJSON() ([]byte, error) {
+func (set Set) MarshalJSON() ([]byte, error) {
 	return json.Marshal(set.Slice())
 }
 
diff --git a/container/gset/gset_int_set.go b/container/gset/gset_int_set.go
index efc75bbff..cda8a6711 100644
--- a/container/gset/gset_int_set.go
+++ b/container/gset/gset_int_set.go
@@ -426,7 +426,7 @@ func (set *IntSet) Walk(f func(item int) int) *IntSet {
 }
 
 // MarshalJSON implements the interface MarshalJSON for json.Marshal.
-func (set *IntSet) MarshalJSON() ([]byte, error) {
+func (set IntSet) MarshalJSON() ([]byte, error) {
 	return json.Marshal(set.Slice())
 }
 
diff --git a/container/gset/gset_str_set.go b/container/gset/gset_str_set.go
index 42c57fd07..3d13de1e4 100644
--- a/container/gset/gset_str_set.go
+++ b/container/gset/gset_str_set.go
@@ -454,7 +454,7 @@ func (set *StrSet) Walk(f func(item string) string) *StrSet {
 }
 
 // MarshalJSON implements the interface MarshalJSON for json.Marshal.
-func (set *StrSet) MarshalJSON() ([]byte, error) {
+func (set StrSet) MarshalJSON() ([]byte, error) {
 	return json.Marshal(set.Slice())
 }
 
diff --git a/container/gtree/gtree_avltree.go b/container/gtree/gtree_avltree.go
index 421865dbe..23c9fa0c8 100644
--- a/container/gtree/gtree_avltree.go
+++ b/container/gtree/gtree_avltree.go
@@ -780,7 +780,7 @@ func output(node *AVLTreeNode, prefix string, isTail bool, str *string) {
 }
 
 // MarshalJSON implements the interface MarshalJSON for json.Marshal.
-func (tree *AVLTree) MarshalJSON() ([]byte, error) {
+func (tree AVLTree) MarshalJSON() ([]byte, error) {
 	return json.Marshal(tree.MapStrAny())
 }
 
diff --git a/container/gtree/gtree_btree.go b/container/gtree/gtree_btree.go
index fff430b3e..87f10ddbc 100644
--- a/container/gtree/gtree_btree.go
+++ b/container/gtree/gtree_btree.go
@@ -944,7 +944,7 @@ func (tree *BTree) deleteChild(node *BTreeNode, index int) {
 }
 
 // MarshalJSON implements the interface MarshalJSON for json.Marshal.
-func (tree *BTree) MarshalJSON() ([]byte, error) {
+func (tree BTree) MarshalJSON() ([]byte, error) {
 	return json.Marshal(tree.MapStrAny())
 }
 
diff --git a/container/gtree/gtree_redblacktree.go b/container/gtree/gtree_redblacktree.go
index 2433648a3..01d875dcc 100644
--- a/container/gtree/gtree_redblacktree.go
+++ b/container/gtree/gtree_redblacktree.go
@@ -925,7 +925,7 @@ func (tree *RedBlackTree) nodeColor(node *RedBlackTreeNode) color {
 }
 
 // MarshalJSON implements the interface MarshalJSON for json.Marshal.
-func (tree *RedBlackTree) MarshalJSON() ([]byte, error) {
+func (tree RedBlackTree) MarshalJSON() ([]byte, error) {
 	return json.Marshal(gconv.Map(tree.Map()))
 }
 
diff --git a/container/gtype/gtype_bool.go b/container/gtype/gtype_bool.go
index d1b00e3dd..42d0c6a33 100644
--- a/container/gtype/gtype_bool.go
+++ b/container/gtype/gtype_bool.go
@@ -78,7 +78,7 @@ func (v *Bool) String() string {
 }
 
 // MarshalJSON implements the interface MarshalJSON for json.Marshal.
-func (v *Bool) MarshalJSON() ([]byte, error) {
+func (v Bool) MarshalJSON() ([]byte, error) {
 	if v.Val() {
 		return bytesTrue, nil
 	}
diff --git a/container/gtype/gtype_byte.go b/container/gtype/gtype_byte.go
index 5a8ffb385..87e41d29c 100644
--- a/container/gtype/gtype_byte.go
+++ b/container/gtype/gtype_byte.go
@@ -60,7 +60,7 @@ func (v *Byte) String() string {
 }
 
 // MarshalJSON implements the interface MarshalJSON for json.Marshal.
-func (v *Byte) MarshalJSON() ([]byte, error) {
+func (v Byte) MarshalJSON() ([]byte, error) {
 	return []byte(strconv.FormatUint(uint64(v.Val()), 10)), nil
 }
 
diff --git a/container/gtype/gtype_bytes.go b/container/gtype/gtype_bytes.go
index 0f8e4095c..6b69febfe 100644
--- a/container/gtype/gtype_bytes.go
+++ b/container/gtype/gtype_bytes.go
@@ -57,7 +57,7 @@ func (v *Bytes) String() string {
 }
 
 // MarshalJSON implements the interface MarshalJSON for json.Marshal.
-func (v *Bytes) MarshalJSON() ([]byte, error) {
+func (v Bytes) MarshalJSON() ([]byte, error) {
 	val := v.Val()
 	dst := make([]byte, base64.StdEncoding.EncodedLen(len(val)))
 	base64.StdEncoding.Encode(dst, val)
diff --git a/container/gtype/gtype_float32.go b/container/gtype/gtype_float32.go
index fc096c8d7..961a822bc 100644
--- a/container/gtype/gtype_float32.go
+++ b/container/gtype/gtype_float32.go
@@ -72,7 +72,7 @@ func (v *Float32) String() string {
 }
 
 // MarshalJSON implements the interface MarshalJSON for json.Marshal.
-func (v *Float32) MarshalJSON() ([]byte, error) {
+func (v Float32) MarshalJSON() ([]byte, error) {
 	return []byte(strconv.FormatFloat(float64(v.Val()), 'g', -1, 32)), nil
 }
 
diff --git a/container/gtype/gtype_float64.go b/container/gtype/gtype_float64.go
index fd5a2e99e..2fc869355 100644
--- a/container/gtype/gtype_float64.go
+++ b/container/gtype/gtype_float64.go
@@ -72,7 +72,7 @@ func (v *Float64) String() string {
 }
 
 // MarshalJSON implements the interface MarshalJSON for json.Marshal.
-func (v *Float64) MarshalJSON() ([]byte, error) {
+func (v Float64) MarshalJSON() ([]byte, error) {
 	return []byte(strconv.FormatFloat(v.Val(), 'g', -1, 64)), nil
 }
 
diff --git a/container/gtype/gtype_int.go b/container/gtype/gtype_int.go
index 9e6dbeaa6..2114b8822 100644
--- a/container/gtype/gtype_int.go
+++ b/container/gtype/gtype_int.go
@@ -60,7 +60,7 @@ func (v *Int) String() string {
 }
 
 // MarshalJSON implements the interface MarshalJSON for json.Marshal.
-func (v *Int) MarshalJSON() ([]byte, error) {
+func (v Int) MarshalJSON() ([]byte, error) {
 	return []byte(strconv.Itoa(v.Val())), nil
 }
 
diff --git a/container/gtype/gtype_int32.go b/container/gtype/gtype_int32.go
index 849f3dcd8..99a3188a0 100644
--- a/container/gtype/gtype_int32.go
+++ b/container/gtype/gtype_int32.go
@@ -60,7 +60,7 @@ func (v *Int32) String() string {
 }
 
 // MarshalJSON implements the interface MarshalJSON for json.Marshal.
-func (v *Int32) MarshalJSON() ([]byte, error) {
+func (v Int32) MarshalJSON() ([]byte, error) {
 	return []byte(strconv.Itoa(int(v.Val()))), nil
 }
 
diff --git a/container/gtype/gtype_int64.go b/container/gtype/gtype_int64.go
index 3bf12afef..85558aceb 100644
--- a/container/gtype/gtype_int64.go
+++ b/container/gtype/gtype_int64.go
@@ -60,7 +60,7 @@ func (v *Int64) String() string {
 }
 
 // MarshalJSON implements the interface MarshalJSON for json.Marshal.
-func (v *Int64) MarshalJSON() ([]byte, error) {
+func (v Int64) MarshalJSON() ([]byte, error) {
 	return []byte(strconv.FormatInt(v.Val(), 10)), nil
 }
 
diff --git a/container/gtype/gtype_interface.go b/container/gtype/gtype_interface.go
index a9ad7877b..04f95d3c5 100644
--- a/container/gtype/gtype_interface.go
+++ b/container/gtype/gtype_interface.go
@@ -52,7 +52,7 @@ func (v *Interface) String() string {
 }
 
 // MarshalJSON implements the interface MarshalJSON for json.Marshal.
-func (v *Interface) MarshalJSON() ([]byte, error) {
+func (v Interface) MarshalJSON() ([]byte, error) {
 	return json.Marshal(v.Val())
 }
 
diff --git a/container/gtype/gtype_string.go b/container/gtype/gtype_string.go
index e22f680b5..f3e442eb2 100644
--- a/container/gtype/gtype_string.go
+++ b/container/gtype/gtype_string.go
@@ -54,7 +54,7 @@ func (v *String) String() string {
 }
 
 // MarshalJSON implements the interface MarshalJSON for json.Marshal.
-func (v *String) MarshalJSON() ([]byte, error) {
+func (v String) MarshalJSON() ([]byte, error) {
 	return []byte(`"` + v.Val() + `"`), nil
 }
 
diff --git a/container/gtype/gtype_uint.go b/container/gtype/gtype_uint.go
index e9dada149..763d90f6a 100644
--- a/container/gtype/gtype_uint.go
+++ b/container/gtype/gtype_uint.go
@@ -60,7 +60,7 @@ func (v *Uint) String() string {
 }
 
 // MarshalJSON implements the interface MarshalJSON for json.Marshal.
-func (v *Uint) MarshalJSON() ([]byte, error) {
+func (v Uint) MarshalJSON() ([]byte, error) {
 	return []byte(strconv.FormatUint(uint64(v.Val()), 10)), nil
 }
 
diff --git a/container/gtype/gtype_uint32.go b/container/gtype/gtype_uint32.go
index 1e52377e3..b877b56c4 100644
--- a/container/gtype/gtype_uint32.go
+++ b/container/gtype/gtype_uint32.go
@@ -60,7 +60,7 @@ func (v *Uint32) String() string {
 }
 
 // MarshalJSON implements the interface MarshalJSON for json.Marshal.
-func (v *Uint32) MarshalJSON() ([]byte, error) {
+func (v Uint32) MarshalJSON() ([]byte, error) {
 	return []byte(strconv.FormatUint(uint64(v.Val()), 10)), nil
 }
 
diff --git a/container/gtype/gtype_uint64.go b/container/gtype/gtype_uint64.go
index f7cda75bb..71a7bd202 100644
--- a/container/gtype/gtype_uint64.go
+++ b/container/gtype/gtype_uint64.go
@@ -60,7 +60,7 @@ func (v *Uint64) String() string {
 }
 
 // MarshalJSON implements the interface MarshalJSON for json.Marshal.
-func (v *Uint64) MarshalJSON() ([]byte, error) {
+func (v Uint64) MarshalJSON() ([]byte, error) {
 	return []byte(strconv.FormatUint(v.Val(), 10)), nil
 }
 
diff --git a/container/gvar/gvar.go b/container/gvar/gvar.go
index f9d79adab..f17afae55 100644
--- a/container/gvar/gvar.go
+++ b/container/gvar/gvar.go
@@ -169,7 +169,7 @@ func (v *Var) GTime(format ...string) *gtime.Time {
 }
 
 // MarshalJSON implements the interface MarshalJSON for json.Marshal.
-func (v *Var) MarshalJSON() ([]byte, error) {
+func (v Var) MarshalJSON() ([]byte, error) {
 	return json.Marshal(v.Val())
 }
 
diff --git a/database/gdb/gdb_core.go b/database/gdb/gdb_core.go
index 18feebc59..594145c96 100644
--- a/database/gdb/gdb_core.go
+++ b/database/gdb/gdb_core.go
@@ -633,7 +633,7 @@ func (c *Core) DoDelete(ctx context.Context, link Link, table string, condition
 //
 // Note that this interface implements mainly for workaround for a json infinite loop bug
 // of Golang version < v1.14.
-func (c *Core) MarshalJSON() ([]byte, error) {
+func (c Core) MarshalJSON() ([]byte, error) {
 	return []byte(fmt.Sprintf(`%+v`, c)), nil
 }
 
diff --git a/encoding/gjson/gjson_implements.go b/encoding/gjson/gjson_implements.go
index a907e03f6..60e146885 100644
--- a/encoding/gjson/gjson_implements.go
+++ b/encoding/gjson/gjson_implements.go
@@ -7,7 +7,7 @@
 package gjson
 
 // MarshalJSON implements the interface MarshalJSON for json.Marshal.
-func (j *Json) MarshalJSON() ([]byte, error) {
+func (j Json) MarshalJSON() ([]byte, error) {
 	return j.ToJson()
 }
 
diff --git a/errors/gerror/gerror_error.go b/errors/gerror/gerror_error.go
index e0f27bb4d..c69f01836 100644
--- a/errors/gerror/gerror_error.go
+++ b/errors/gerror/gerror_error.go
@@ -185,7 +185,7 @@ func (err *Error) SetCode(code gcode.Code) {
 
 // MarshalJSON implements the interface MarshalJSON for json.Marshal.
 // Note that do not use pointer as its receiver here.
-func (err *Error) MarshalJSON() ([]byte, error) {
+func (err Error) MarshalJSON() ([]byte, error) {
 	return []byte(`"` + err.Error() + `"`), nil
 }
 
diff --git a/net/ghttp/ghttp_server_router_serve.go b/net/ghttp/ghttp_server_router_serve.go
index 8ae683d97..999dda6c7 100644
--- a/net/ghttp/ghttp_server_router_serve.go
+++ b/net/ghttp/ghttp_server_router_serve.go
@@ -220,7 +220,7 @@ func (s *Server) searchHandlers(method, path, domain string) (parsedItems []*han
 }
 
 // MarshalJSON implements the interface MarshalJSON for json.Marshal.
-func (item *handlerItem) MarshalJSON() ([]byte, error) {
+func (item handlerItem) MarshalJSON() ([]byte, error) {
 	switch item.Type {
 	case HandlerTypeHook:
 		return json.Marshal(
@@ -254,6 +254,6 @@ func (item *handlerItem) MarshalJSON() ([]byte, error) {
 }
 
 // MarshalJSON implements the interface MarshalJSON for json.Marshal.
-func (item *handlerParsedItem) MarshalJSON() ([]byte, error) {
+func (item handlerParsedItem) MarshalJSON() ([]byte, error) {
 	return json.Marshal(item.Handler)
 }
diff --git a/os/gcmd/gcmd_parser.go b/os/gcmd/gcmd_parser.go
index 1ed5f28eb..e9be2f129 100644
--- a/os/gcmd/gcmd_parser.go
+++ b/os/gcmd/gcmd_parser.go
@@ -221,7 +221,7 @@ func (p *Parser) GetArgAll() []string {
 }
 
 // MarshalJSON implements the interface MarshalJSON for json.Marshal.
-func (p *Parser) MarshalJSON() ([]byte, error) {
+func (p Parser) MarshalJSON() ([]byte, error) {
 	return json.Marshal(map[string]interface{}{
 		"parsedArgs":       p.parsedArgs,
 		"parsedOptions":    p.parsedOptions,
diff --git a/os/gres/gres_file.go b/os/gres/gres_file.go
index 036337c87..3a826a8cc 100644
--- a/os/gres/gres_file.go
+++ b/os/gres/gres_file.go
@@ -55,7 +55,7 @@ func (f *File) FileInfo() os.FileInfo {
 }
 
 // MarshalJSON implements the interface MarshalJSON for json.Marshal.
-func (f *File) MarshalJSON() ([]byte, error) {
+func (f File) MarshalJSON() ([]byte, error) {
 	info := f.FileInfo()
 	return json.Marshal(map[string]interface{}{
 		"name": f.Name(),
diff --git a/os/gtime/gtime_time.go b/os/gtime/gtime_time.go
index 0854968ed..1d6873aed 100644
--- a/os/gtime/gtime_time.go
+++ b/os/gtime/gtime_time.go
@@ -446,6 +446,8 @@ func (t *Time) EndOfYear() *Time {
 }
 
 // MarshalJSON implements the interface MarshalJSON for json.Marshal.
+// Note that, DO NOT use `(t *Time) MarshalJSON() ([]byte, error)` as it looses interface
+// implement of `MarshalJSON` for struct of Time.
 func (t Time) MarshalJSON() ([]byte, error) {
 	return []byte(`"` + t.String() + `"`), nil
 }
diff --git a/os/gtime/gtime_z_unit_feature_json_test.go b/os/gtime/gtime_z_unit_feature_json_test.go
index 1704ff926..e1e90e7ac 100644
--- a/os/gtime/gtime_z_unit_feature_json_test.go
+++ b/os/gtime/gtime_z_unit_feature_json_test.go
@@ -12,6 +12,7 @@ import (
 	"github.com/gogf/gf/v2/internal/json"
 	"github.com/gogf/gf/v2/os/gtime"
 	"github.com/gogf/gf/v2/test/gtest"
+	"github.com/gogf/gf/v2/util/gconv"
 )
 
 func Test_Json_Pointer(t *testing.T) {
@@ -27,6 +28,21 @@ func Test_Json_Pointer(t *testing.T) {
 		t.Assert(err, nil)
 		t.Assert(j, `{"Time":"2006-01-02 15:04:05"}`)
 	})
+	// Marshal struct with embedded.
+	gtest.C(t, func(t *gtest.T) {
+		type Time struct {
+			MyTime *gtime.Time
+		}
+		type T struct {
+			Time
+		}
+		t1 := new(T)
+		s := "2006-01-02 15:04:05"
+		t1.MyTime = gtime.NewFromStr(s)
+		j, err := json.Marshal(gconv.Map(t1))
+		t.Assert(err, nil)
+		t.Assert(j, `{"MyTime":"2006-01-02 15:04:05"}`)
+	})
 	// Marshal nil
 	gtest.C(t, func(t *gtest.T) {
 		type T struct {