diff --git a/github/github-accessors.go b/github/github-accessors.go
index b470ba80255..2650f7f1f44 100644
--- a/github/github-accessors.go
+++ b/github/github-accessors.go
@@ -23574,6 +23574,14 @@ func (r *RepositoryRelease) GetID() int64 {
 	return *r.ID
 }
 
+// GetImmutable returns the Immutable field if it's non-nil, zero value otherwise.
+func (r *RepositoryRelease) GetImmutable() bool {
+	if r == nil || r.Immutable == nil {
+		return false
+	}
+	return *r.Immutable
+}
+
 // GetMakeLatest returns the MakeLatest field if it's non-nil, zero value otherwise.
 func (r *RepositoryRelease) GetMakeLatest() string {
 	if r == nil || r.MakeLatest == nil {
diff --git a/github/github-accessors_test.go b/github/github-accessors_test.go
index d61b00e5f69..f09107fd157 100644
--- a/github/github-accessors_test.go
+++ b/github/github-accessors_test.go
@@ -30445,6 +30445,17 @@ func TestRepositoryRelease_GetID(tt *testing.T) {
 	r.GetID()
 }
 
+func TestRepositoryRelease_GetImmutable(tt *testing.T) {
+	tt.Parallel()
+	var zeroValue bool
+	r := &RepositoryRelease{Immutable: &zeroValue}
+	r.GetImmutable()
+	r = &RepositoryRelease{}
+	r.GetImmutable()
+	r = nil
+	r.GetImmutable()
+}
+
 func TestRepositoryRelease_GetMakeLatest(tt *testing.T) {
 	tt.Parallel()
 	var zeroValue string
diff --git a/github/github-stringify_test.go b/github/github-stringify_test.go
index b246f0bc35a..fe696c3f7a0 100644
--- a/github/github-stringify_test.go
+++ b/github/github-stringify_test.go
@@ -2018,8 +2018,9 @@ func TestRepositoryRelease_String(t *testing.T) {
 		TarballURL:             Ptr(""),
 		Author:                 &User{},
 		NodeID:                 Ptr(""),
+		Immutable:              Ptr(false),
 	}
-	want := `github.RepositoryRelease{TagName:"", TargetCommitish:"", Name:"", Body:"", Draft:false, Prerelease:false, MakeLatest:"", DiscussionCategoryName:"", GenerateReleaseNotes:false, ID:0, CreatedAt:github.Timestamp{0001-01-01 00:00:00 +0000 UTC}, PublishedAt:github.Timestamp{0001-01-01 00:00:00 +0000 UTC}, URL:"", HTMLURL:"", AssetsURL:"", UploadURL:"", ZipballURL:"", TarballURL:"", Author:github.User{}, NodeID:""}`
+	want := `github.RepositoryRelease{TagName:"", TargetCommitish:"", Name:"", Body:"", Draft:false, Prerelease:false, MakeLatest:"", DiscussionCategoryName:"", GenerateReleaseNotes:false, ID:0, CreatedAt:github.Timestamp{0001-01-01 00:00:00 +0000 UTC}, PublishedAt:github.Timestamp{0001-01-01 00:00:00 +0000 UTC}, URL:"", HTMLURL:"", AssetsURL:"", UploadURL:"", ZipballURL:"", TarballURL:"", Author:github.User{}, NodeID:"", Immutable:false}`
 	if got := v.String(); got != want {
 		t.Errorf("RepositoryRelease.String = %v, want %v", got, want)
 	}
diff --git a/github/repos_releases.go b/github/repos_releases.go
index 87056071c9f..db0f0d9279f 100644
--- a/github/repos_releases.go
+++ b/github/repos_releases.go
@@ -45,6 +45,7 @@ type RepositoryRelease struct {
 	TarballURL  *string         `json:"tarball_url,omitempty"`
 	Author      *User           `json:"author,omitempty"`
 	NodeID      *string         `json:"node_id,omitempty"`
+	Immutable   *bool           `json:"immutable,omitempty"`
 }
 
 func (r RepositoryRelease) String() string {
diff --git a/github/repos_releases_test.go b/github/repos_releases_test.go
index 6416086f346..ad147898ee3 100644
--- a/github/repos_releases_test.go
+++ b/github/repos_releases_test.go
@@ -221,6 +221,7 @@ func TestRepositoriesService_CreateRelease(t *testing.T) {
 		TarballURL:  Ptr("http://tarballurl/"),
 		Author:      &User{Name: Ptr("octocat")},
 		NodeID:      Ptr("nodeid"),
+		Immutable:   Ptr(false),
 	}
 
 	mux.HandleFunc("/repos/o/r/releases", func(w http.ResponseWriter, r *http.Request) {
@@ -290,6 +291,7 @@ func TestRepositoriesService_EditRelease(t *testing.T) {
 		TarballURL:           Ptr("http://tarballurl/"),
 		Author:               &User{Name: Ptr("octocat")},
 		NodeID:               Ptr("nodeid"),
+		Immutable:            Ptr(false),
 	}
 
 	mux.HandleFunc("/repos/o/r/releases/1", func(w http.ResponseWriter, r *http.Request) {
@@ -875,6 +877,7 @@ func TestRepositoryRelease_Marshal(t *testing.T) {
 		TarballURL:             Ptr("turl"),
 		Author:                 &User{ID: Ptr(int64(1))},
 		NodeID:                 Ptr("nid"),
+		Immutable:              Ptr(true),
 	}
 
 	want := `{
@@ -903,7 +906,8 @@ func TestRepositoryRelease_Marshal(t *testing.T) {
 		"author": {
 			"id": 1
 		},
-		"node_id": "nid"
+		"node_id": "nid",
+		"immutable": true
 	}`
 
 	testJSONMarshal(t, u, want)