diff --git a/encode_test.go b/encode_test.go
index 5b271b0..98f71b0 100644
--- a/encode_test.go
+++ b/encode_test.go
@@ -191,6 +191,59 @@ func Test_Marshal(t *testing.T) {
 				})
 			})
 		})
+
+		t.Run("embedded with tag", func(t *testing.T) {
+			type T struct {
+				A string `json:"a"`
+			}
+			type U struct {
+				*T `json:"t"`
+				B  string `json:"b"`
+			}
+			type T2 struct {
+				A string `json:"a,omitempty"`
+			}
+			type U2 struct {
+				*T2 `json:"t,omitempty"`
+				B   string `json:"b,omitempty"`
+			}
+			t.Run("exists field", func(t *testing.T) {
+				bytes, err := json.Marshal(&U{
+					T: &T{
+						A: "aaa",
+					},
+					B: "bbb",
+				})
+				assertErr(t, err)
+				assertEq(t, "embedded", `{"t":{"a":"aaa"},"b":"bbb"}`, string(bytes))
+				t.Run("omitempty", func(t *testing.T) {
+					bytes, err := json.Marshal(&U2{
+						T2: &T2{
+							A: "aaa",
+						},
+						B: "bbb",
+					})
+					assertErr(t, err)
+					assertEq(t, "embedded", `{"t":{"a":"aaa"},"b":"bbb"}`, string(bytes))
+				})
+			})
+
+			t.Run("none field", func(t *testing.T) {
+				bytes, err := json.Marshal(&U{
+					B: "bbb",
+				})
+				assertErr(t, err)
+				assertEq(t, "embedded", `{"t":null,"b":"bbb"}`, string(bytes))
+				t.Run("omitempty", func(t *testing.T) {
+					bytes, err := json.Marshal(&U2{
+						B: "bbb",
+					})
+					assertErr(t, err)
+					assertEq(t, "embedded", `{"b":"bbb"}`, string(bytes))
+				})
+			})
+		})
+
 		t.Run("omitempty", func(t *testing.T) {
 			type T struct {
 				A int                    `json:",omitempty"`
diff --git a/internal/cmd/generator/vm.go.tmpl b/internal/cmd/generator/vm.go.tmpl
index 78da5e4..f2c992a 100644
--- a/internal/cmd/generator/vm.go.tmpl
+++ b/internal/cmd/generator/vm.go.tmpl
@@ -578,8 +578,10 @@ func Run(ctx *encoder.RuntimeContext, b []byte, codeSet *encoder.OpcodeSet) ([]b
 			if code.Flags&encoder.AnonymousHeadFlags == 0 {
 				b = appendStructHead(ctx, b)
 			}
-			if (code.Flags&encoder.AnonymousKeyFlags) == 0 && len(code.Key) > 0 {
-				b = appendStructKey(ctx, code, b)
+			if len(code.Key) > 0 {
+				if (code.Flags&encoder.IsTaggedKeyFlags) != 0 || code.Flags&encoder.AnonymousKeyFlags == 0 {
+					b = appendStructKey(ctx, code, b)
+				}
 			}
 			p += uintptr(code.Offset)
 			code = code.Next
diff --git a/internal/encoder/vm/vm.go b/internal/encoder/vm/vm.go
index 78da5e4..f2c992a 100644
--- a/internal/encoder/vm/vm.go
+++ b/internal/encoder/vm/vm.go
@@ -578,8 +578,10 @@ func Run(ctx *encoder.RuntimeContext, b []byte, codeSet *encoder.OpcodeSet) ([]b
 			if code.Flags&encoder.AnonymousHeadFlags == 0 {
 				b = appendStructHead(ctx, b)
 			}
-			if (code.Flags&encoder.AnonymousKeyFlags) == 0 && len(code.Key) > 0 {
-				b = appendStructKey(ctx, code, b)
+			if len(code.Key) > 0 {
+				if (code.Flags&encoder.IsTaggedKeyFlags) != 0 || code.Flags&encoder.AnonymousKeyFlags == 0 {
+					b = appendStructKey(ctx, code, b)
+				}
 			}
 			p += uintptr(code.Offset)
 			code = code.Next
diff --git a/internal/encoder/vm_color/vm.go b/internal/encoder/vm_color/vm.go
index 0d4c472..70de3e7 100644
--- a/internal/encoder/vm_color/vm.go
+++ b/internal/encoder/vm_color/vm.go
@@ -578,8 +578,10 @@ func Run(ctx *encoder.RuntimeContext, b []byte, codeSet *encoder.OpcodeSet) ([]b
 			if code.Flags&encoder.AnonymousHeadFlags == 0 {
 				b = appendStructHead(ctx, b)
 			}
-			if (code.Flags&encoder.AnonymousKeyFlags) == 0 && len(code.Key) > 0 {
-				b = appendStructKey(ctx, code, b)
+			if len(code.Key) > 0 {
+				if (code.Flags&encoder.IsTaggedKeyFlags) != 0 || code.Flags&encoder.AnonymousKeyFlags == 0 {
+					b = appendStructKey(ctx, code, b)
+				}
 			}
 			p += uintptr(code.Offset)
 			code = code.Next
diff --git a/internal/encoder/vm_color_indent/vm.go b/internal/encoder/vm_color_indent/vm.go
index de8b858..2d014e5 100644
--- a/internal/encoder/vm_color_indent/vm.go
+++ b/internal/encoder/vm_color_indent/vm.go
@@ -578,8 +578,10 @@ func Run(ctx *encoder.RuntimeContext, b []byte, codeSet *encoder.OpcodeSet) ([]b
 			if code.Flags&encoder.AnonymousHeadFlags == 0 {
 				b = appendStructHead(ctx, b)
 			}
-			if (code.Flags&encoder.AnonymousKeyFlags) == 0 && len(code.Key) > 0 {
-				b = appendStructKey(ctx, code, b)
+			if len(code.Key) > 0 {
+				if (code.Flags&encoder.IsTaggedKeyFlags) != 0 || code.Flags&encoder.AnonymousKeyFlags == 0 {
+					b = appendStructKey(ctx, code, b)
+				}
 			}
 			p += uintptr(code.Offset)
 			code = code.Next
diff --git a/internal/encoder/vm_indent/vm.go b/internal/encoder/vm_indent/vm.go
index d10ce75..25d2ebc 100644
--- a/internal/encoder/vm_indent/vm.go
+++ b/internal/encoder/vm_indent/vm.go
@@ -578,8 +578,10 @@ func Run(ctx *encoder.RuntimeContext, b []byte, codeSet *encoder.OpcodeSet) ([]b
 			if code.Flags&encoder.AnonymousHeadFlags == 0 {
 				b = appendStructHead(ctx, b)
 			}
-			if (code.Flags&encoder.AnonymousKeyFlags) == 0 && len(code.Key) > 0 {
-				b = appendStructKey(ctx, code, b)
+			if len(code.Key) > 0 {
+				if (code.Flags&encoder.IsTaggedKeyFlags) != 0 || code.Flags&encoder.AnonymousKeyFlags == 0 {
+					b = appendStructKey(ctx, code, b)
+				}
 			}
 			p += uintptr(code.Offset)
 			code = code.Next