diff --git a/CHANGELOG.md b/CHANGELOG.md
index 40c1511..144ffd2 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -191,4 +191,10 @@
   - Fix create transcribes error
   - Create speech
 - Embedding 
-  - Add new Model
\ No newline at end of file
+  - Add new Model
+- Thread
+  - Create a thread.
+  - Retrieves a thread.
+  - Modifies a thread.
+  - Delete a thread.
+  
\ No newline at end of file
diff --git a/lib/src/model/file/request/upload_file.dart b/lib/src/model/file/request/upload_file.dart
index a41a952..857a188 100644
--- a/lib/src/model/file/request/upload_file.dart
+++ b/lib/src/model/file/request/upload_file.dart
@@ -19,7 +19,7 @@ class UploadFile {
 
   Future<FormData> getForm() async {
     return FormData.fromMap({
-      'file': File(file.path).existsSync()
+      'file': (await File(file.path).exists())
           ? await MultipartFile.fromFile(file.path, filename: file.name)
           : null,
       'purpose': purpose,
diff --git a/lib/src/model/thread/request/thread_request.dart b/lib/src/model/thread/request/thread_request.dart
new file mode 100644
index 0000000..18153cf
--- /dev/null
+++ b/lib/src/model/thread/request/thread_request.dart
@@ -0,0 +1,18 @@
+class ThreadRequest {
+  final List<Map<String, dynamic>>? messages;
+
+  ///Set of 16 key-value pairs that can be attached to an object.
+  /// This can be useful for storing additional information about the
+  /// object in a structured format. Keys can be a maximum of 64
+  /// characters long and values can be a maxium of 512 characters long.
+  /// [metadata]
+  final Map<String, dynamic>? metadata;
+
+  ThreadRequest({this.messages, this.metadata});
+
+  Map<String, dynamic> toJson() => Map.of({
+        'messages': messages,
+        'metadata': metadata,
+      })
+        ..removeWhere((_, value) => value == null);
+}
diff --git a/lib/src/model/thread/response/thread_delete_response.dart b/lib/src/model/thread/response/thread_delete_response.dart
new file mode 100644
index 0000000..4432706
--- /dev/null
+++ b/lib/src/model/thread/response/thread_delete_response.dart
@@ -0,0 +1,24 @@
+class ThreadDeleteResponse {
+  ThreadDeleteResponse({
+    required this.deleted,
+    required this.id,
+    required this.object,
+  });
+
+  bool deleted;
+  String id;
+  String object;
+
+  factory ThreadDeleteResponse.fromJson(Map<String, dynamic> json) =>
+      ThreadDeleteResponse(
+        deleted: json["deleted"] ?? false,
+        id: json["id"] ?? '',
+        object: json["object"] ?? '',
+      );
+
+  Map<String, dynamic> toJson() => {
+        "deleted": deleted,
+        "id": id,
+        "object": object,
+      };
+}
diff --git a/lib/src/model/thread/response/thread_response.dart b/lib/src/model/thread/response/thread_response.dart
new file mode 100644
index 0000000..65eb4ce
--- /dev/null
+++ b/lib/src/model/thread/response/thread_response.dart
@@ -0,0 +1,27 @@
+class ThreadResponse {
+  ThreadResponse({
+    required this.metadata,
+    required this.createdAt,
+    required this.id,
+    required this.object,
+  });
+
+  Map<String, dynamic> metadata;
+  int createdAt;
+  String id;
+  String object;
+
+  factory ThreadResponse.fromJson(Map<String, dynamic> json) => ThreadResponse(
+        metadata: json["metadata"] ?? {},
+        createdAt: json["created_at"] ?? 0,
+        id: json["id"] ?? '',
+        object: json["object"] ?? '',
+      );
+
+  Map<String, dynamic> toJson() => {
+        "metadata": metadata,
+        "created_at": createdAt,
+        "id": id,
+        "object": object,
+      };
+}
diff --git a/lib/src/openai.dart b/lib/src/openai.dart
index dc4f161..48afcf4 100644
--- a/lib/src/openai.dart
+++ b/lib/src/openai.dart
@@ -18,6 +18,7 @@ import 'package:chat_gpt_sdk/src/model/gen_image/response/gen_img_response.dart'
 import 'package:chat_gpt_sdk/src/model/openai_engine/engine_model.dart';
 import 'package:chat_gpt_sdk/src/model/openai_model/openai_model.dart';
 import 'package:chat_gpt_sdk/src/moderation.dart';
+import 'package:chat_gpt_sdk/src/threads.dart';
 import 'package:chat_gpt_sdk/src/utils/constants.dart';
 import 'package:chat_gpt_sdk/src/utils/token_builder.dart';
 import 'package:dio/dio.dart';
@@ -232,4 +233,6 @@ class OpenAI implements IOpenAI {
 
   ///Assistants
   Assistants get assistant => Assistants(_client);
+
+  Threads get threads => Threads(client: _client);
 }
diff --git a/lib/src/threads.dart b/lib/src/threads.dart
new file mode 100644
index 0000000..efe1d50
--- /dev/null
+++ b/lib/src/threads.dart
@@ -0,0 +1,70 @@
+import 'package:chat_gpt_sdk/src/client/openai_client.dart';
+import 'package:chat_gpt_sdk/src/model/thread/request/thread_request.dart';
+import 'package:chat_gpt_sdk/src/model/thread/response/thread_delete_response.dart';
+import 'package:chat_gpt_sdk/src/model/thread/response/thread_response.dart';
+import 'package:chat_gpt_sdk/src/utils/constants.dart';
+
+class Threads {
+  final OpenAIClient _client;
+
+  Threads({required OpenAIClient client}) : _client = client;
+
+  Map<String, String> _headers = {'OpenAI-Beta': 'assistants=v1'};
+  Map<String, String> get getHeader => _headers;
+
+  void addHeader(Map<String, String> mHeader) {
+    if (mHeader == {}) return;
+
+    _headers.addAll(mHeader);
+  }
+
+  ///Create a thread.
+  /// [createThread]
+  Future<ThreadResponse> createThread({
+    ThreadRequest? request,
+  }) {
+    return _client.post(
+      _client.apiUrl + kThread,
+      request == null ? {} : request.toJson(),
+      headers: _headers,
+      onSuccess: ThreadResponse.fromJson,
+      onCancel: (cancelData) => null,
+    );
+  }
+
+  ///The ID of the thread to retrieve.[threadId]
+  /// [retrieveThread]
+  Future<ThreadResponse> retrieveThread({
+    required String threadId,
+  }) {
+    return _client.get(
+      _client.apiUrl + kThread + "/$threadId",
+      headers: _headers,
+      onSuccess: ThreadResponse.fromJson,
+      onCancel: (cancelData) => null,
+    );
+  }
+
+  Future<ThreadResponse> modifyThread({
+    required String threadId,
+    required Map<String, dynamic> metadata,
+  }) {
+    return _client.post(
+      _client.apiUrl + kThread + "/$threadId",
+      metadata,
+      headers: _headers,
+      onSuccess: ThreadResponse.fromJson,
+      onCancel: (cancelData) => null,
+    );
+  }
+
+  Future<ThreadDeleteResponse> deleteThread({
+    required String threadId,
+  }) {
+    return _client.delete(
+      _client.apiUrl + kThread + "/$threadId",
+      onSuccess: ThreadDeleteResponse.fromJson,
+      onCancel: (cancelData) => null,
+    );
+  }
+}
diff --git a/lib/src/utils/constants.dart b/lib/src/utils/constants.dart
index 316d590..7584718 100644
--- a/lib/src/utils/constants.dart
+++ b/lib/src/utils/constants.dart
@@ -39,6 +39,9 @@ const kFile = 'files';
 const kFineTune = 'fine-tunes';
 const kFineTuneJob = '$kFineTune/jobs';
 
+///threads
+const kThread = 'threads';
+
 /// fine tune model
 const kFineTuneModel = 'models';