diff --git a/example_protobuf/lib/example.dart b/example_protobuf/lib/example.dart
index 817a15526..47407f43a 100644
--- a/example_protobuf/lib/example.dart
+++ b/example_protobuf/lib/example.dart
@@ -2,7 +2,8 @@ import 'package:dio/dio.dart';
 import 'package:retrofit/retrofit.dart';
 import 'package:flutter/foundation.dart';
 
-import 'proto/query.pbserver.dart';
+import 'proto/params.pbserver.dart';
+import 'proto/result.pbserver.dart';
 
 part 'example.g.dart';
 
@@ -10,10 +11,9 @@ part 'example.g.dart';
 abstract class RestClient {
   factory RestClient(Dio dio, {String baseUrl}) = _RestClient;
 
-  @GET("/tags")
+  @POST("/tags")
   Future<Result> getProtoBufInt(@Body() Params message);
 
-  
-  @GET("/tags1")
+  @POST("/tags1")
   Future<List<int>> getMessage(@Body() Params message);
 }
diff --git a/example_protobuf/lib/proto/params.pb.dart b/example_protobuf/lib/proto/params.pb.dart
new file mode 100644
index 000000000..9934159bf
--- /dev/null
+++ b/example_protobuf/lib/proto/params.pb.dart
@@ -0,0 +1,68 @@
+//
+//  Generated code. Do not modify.
+//  source: proto/params.proto
+//
+// @dart = 2.12
+
+// ignore_for_file: annotate_overrides, camel_case_types, comment_references
+// ignore_for_file: constant_identifier_names, library_prefixes
+// ignore_for_file: non_constant_identifier_names, prefer_final_fields
+// ignore_for_file: unnecessary_import, unnecessary_this, unused_import
+
+import 'dart:core' as $core;
+
+import 'package:protobuf/protobuf.dart' as $pb;
+
+class Params extends $pb.GeneratedMessage {
+  factory Params({
+    $core.String? key,
+  }) {
+    final $result = create();
+    if (key != null) {
+      $result.key = key;
+    }
+    return $result;
+  }
+  Params._() : super();
+  factory Params.fromBuffer($core.List<$core.int> i, [$pb.ExtensionRegistry r = $pb.ExtensionRegistry.EMPTY]) => create()..mergeFromBuffer(i, r);
+  factory Params.fromJson($core.String i, [$pb.ExtensionRegistry r = $pb.ExtensionRegistry.EMPTY]) => create()..mergeFromJson(i, r);
+
+  static final $pb.BuilderInfo _i = $pb.BuilderInfo(_omitMessageNames ? '' : 'Params', package: const $pb.PackageName(_omitMessageNames ? '' : 'examples.enumerations'), createEmptyInstance: create)
+    ..aOS(1, _omitFieldNames ? '' : 'key')
+    ..hasRequiredFields = false
+  ;
+
+  @$core.Deprecated(
+  'Using this can add significant overhead to your binary. '
+  'Use [GeneratedMessageGenericExtensions.deepCopy] instead. '
+  'Will be removed in next major version')
+  Params clone() => Params()..mergeFromMessage(this);
+  @$core.Deprecated(
+  'Using this can add significant overhead to your binary. '
+  'Use [GeneratedMessageGenericExtensions.rebuild] instead. '
+  'Will be removed in next major version')
+  Params copyWith(void Function(Params) updates) => super.copyWith((message) => updates(message as Params)) as Params;
+
+  $pb.BuilderInfo get info_ => _i;
+
+  @$core.pragma('dart2js:noInline')
+  static Params create() => Params._();
+  Params createEmptyInstance() => create();
+  static $pb.PbList<Params> createRepeated() => $pb.PbList<Params>();
+  @$core.pragma('dart2js:noInline')
+  static Params getDefault() => _defaultInstance ??= $pb.GeneratedMessage.$_defaultFor<Params>(create);
+  static Params? _defaultInstance;
+
+  @$pb.TagNumber(1)
+  $core.String get key => $_getSZ(0);
+  @$pb.TagNumber(1)
+  set key($core.String v) { $_setString(0, v); }
+  @$pb.TagNumber(1)
+  $core.bool hasKey() => $_has(0);
+  @$pb.TagNumber(1)
+  void clearKey() => clearField(1);
+}
+
+
+const _omitFieldNames = $core.bool.fromEnvironment('protobuf.omit_field_names');
+const _omitMessageNames = $core.bool.fromEnvironment('protobuf.omit_message_names');
diff --git a/example_protobuf/lib/proto/query.pbenum.dart b/example_protobuf/lib/proto/params.pbenum.dart
similarity index 91%
rename from example_protobuf/lib/proto/query.pbenum.dart
rename to example_protobuf/lib/proto/params.pbenum.dart
index 3b7684b49..22b016f92 100644
--- a/example_protobuf/lib/proto/query.pbenum.dart
+++ b/example_protobuf/lib/proto/params.pbenum.dart
@@ -1,6 +1,6 @@
 //
 //  Generated code. Do not modify.
-//  source: proto/query.proto
+//  source: proto/params.proto
 //
 // @dart = 2.12
 
diff --git a/example_protobuf/lib/proto/params.pbjson.dart b/example_protobuf/lib/proto/params.pbjson.dart
new file mode 100644
index 000000000..52468d1e1
--- /dev/null
+++ b/example_protobuf/lib/proto/params.pbjson.dart
@@ -0,0 +1,27 @@
+//
+//  Generated code. Do not modify.
+//  source: proto/params.proto
+//
+// @dart = 2.12
+
+// ignore_for_file: annotate_overrides, camel_case_types, comment_references
+// ignore_for_file: constant_identifier_names, library_prefixes
+// ignore_for_file: non_constant_identifier_names, prefer_final_fields
+// ignore_for_file: unnecessary_import, unnecessary_this, unused_import
+
+import 'dart:convert' as $convert;
+import 'dart:core' as $core;
+import 'dart:typed_data' as $typed_data;
+
+@$core.Deprecated('Use paramsDescriptor instead')
+const Params$json = {
+  '1': 'Params',
+  '2': [
+    {'1': 'key', '3': 1, '4': 1, '5': 9, '10': 'key'},
+  ],
+};
+
+/// Descriptor for `Params`. Decode as a `google.protobuf.DescriptorProto`.
+final $typed_data.Uint8List paramsDescriptor = $convert.base64Decode(
+    'CgZQYXJhbXMSEAoDa2V5GAEgASgJUgNrZXk=');
+
diff --git a/example_protobuf/lib/proto/query.pbserver.dart b/example_protobuf/lib/proto/params.pbserver.dart
similarity index 87%
rename from example_protobuf/lib/proto/query.pbserver.dart
rename to example_protobuf/lib/proto/params.pbserver.dart
index 667498118..062bb0e56 100644
--- a/example_protobuf/lib/proto/query.pbserver.dart
+++ b/example_protobuf/lib/proto/params.pbserver.dart
@@ -1,6 +1,6 @@
 //
 //  Generated code. Do not modify.
-//  source: proto/query.proto
+//  source: proto/params.proto
 //
 // @dart = 2.12
 
@@ -10,5 +10,5 @@
 // ignore_for_file: non_constant_identifier_names, prefer_final_fields
 // ignore_for_file: unnecessary_import, unnecessary_this, unused_import
 
-export 'query.pb.dart';
+export 'params.pb.dart';
 
diff --git a/example_protobuf/lib/proto/query.pb.dart b/example_protobuf/lib/proto/result.pb.dart
similarity index 56%
rename from example_protobuf/lib/proto/query.pb.dart
rename to example_protobuf/lib/proto/result.pb.dart
index 0c4313161..588154cf0 100644
--- a/example_protobuf/lib/proto/query.pb.dart
+++ b/example_protobuf/lib/proto/result.pb.dart
@@ -1,6 +1,6 @@
 //
 //  Generated code. Do not modify.
-//  source: proto/query.proto
+//  source: proto/result.proto
 //
 // @dart = 2.12
 
@@ -13,56 +13,6 @@ import 'dart:core' as $core;
 
 import 'package:protobuf/protobuf.dart' as $pb;
 
-class Params extends $pb.GeneratedMessage {
-  factory Params({
-    $core.String? key,
-  }) {
-    final $result = create();
-    if (key != null) {
-      $result.key = key;
-    }
-    return $result;
-  }
-  Params._() : super();
-  factory Params.fromBuffer($core.List<$core.int> i, [$pb.ExtensionRegistry r = $pb.ExtensionRegistry.EMPTY]) => create()..mergeFromBuffer(i, r);
-  factory Params.fromJson($core.String i, [$pb.ExtensionRegistry r = $pb.ExtensionRegistry.EMPTY]) => create()..mergeFromJson(i, r);
-
-  static final $pb.BuilderInfo _i = $pb.BuilderInfo(_omitMessageNames ? '' : 'Params', createEmptyInstance: create)
-    ..aOS(1, _omitFieldNames ? '' : 'key')
-    ..hasRequiredFields = false
-  ;
-
-  @$core.Deprecated(
-  'Using this can add significant overhead to your binary. '
-  'Use [GeneratedMessageGenericExtensions.deepCopy] instead. '
-  'Will be removed in next major version')
-  Params clone() => Params()..mergeFromMessage(this);
-  @$core.Deprecated(
-  'Using this can add significant overhead to your binary. '
-  'Use [GeneratedMessageGenericExtensions.rebuild] instead. '
-  'Will be removed in next major version')
-  Params copyWith(void Function(Params) updates) => super.copyWith((message) => updates(message as Params)) as Params;
-
-  $pb.BuilderInfo get info_ => _i;
-
-  @$core.pragma('dart2js:noInline')
-  static Params create() => Params._();
-  Params createEmptyInstance() => create();
-  static $pb.PbList<Params> createRepeated() => $pb.PbList<Params>();
-  @$core.pragma('dart2js:noInline')
-  static Params getDefault() => _defaultInstance ??= $pb.GeneratedMessage.$_defaultFor<Params>(create);
-  static Params? _defaultInstance;
-
-  @$pb.TagNumber(1)
-  $core.String get key => $_getSZ(0);
-  @$pb.TagNumber(1)
-  set key($core.String v) { $_setString(0, v); }
-  @$pb.TagNumber(1)
-  $core.bool hasKey() => $_has(0);
-  @$pb.TagNumber(1)
-  void clearKey() => clearField(1);
-}
-
 class Result extends $pb.GeneratedMessage {
   factory Result({
     $core.String? value,
diff --git a/example_protobuf/lib/proto/result.pbenum.dart b/example_protobuf/lib/proto/result.pbenum.dart
new file mode 100644
index 000000000..0adb6275d
--- /dev/null
+++ b/example_protobuf/lib/proto/result.pbenum.dart
@@ -0,0 +1,11 @@
+//
+//  Generated code. Do not modify.
+//  source: proto/result.proto
+//
+// @dart = 2.12
+
+// ignore_for_file: annotate_overrides, camel_case_types, comment_references
+// ignore_for_file: constant_identifier_names, library_prefixes
+// ignore_for_file: non_constant_identifier_names, prefer_final_fields
+// ignore_for_file: unnecessary_import, unnecessary_this, unused_import
+
diff --git a/example_protobuf/lib/proto/query.pbjson.dart b/example_protobuf/lib/proto/result.pbjson.dart
similarity index 67%
rename from example_protobuf/lib/proto/query.pbjson.dart
rename to example_protobuf/lib/proto/result.pbjson.dart
index cb9660e45..ea9ab4d80 100644
--- a/example_protobuf/lib/proto/query.pbjson.dart
+++ b/example_protobuf/lib/proto/result.pbjson.dart
@@ -1,6 +1,6 @@
 //
 //  Generated code. Do not modify.
-//  source: proto/query.proto
+//  source: proto/result.proto
 //
 // @dart = 2.12
 
@@ -13,18 +13,6 @@ import 'dart:convert' as $convert;
 import 'dart:core' as $core;
 import 'dart:typed_data' as $typed_data;
 
-@$core.Deprecated('Use paramsDescriptor instead')
-const Params$json = {
-  '1': 'Params',
-  '2': [
-    {'1': 'key', '3': 1, '4': 1, '5': 9, '10': 'key'},
-  ],
-};
-
-/// Descriptor for `Params`. Decode as a `google.protobuf.DescriptorProto`.
-final $typed_data.Uint8List paramsDescriptor = $convert.base64Decode(
-    'CgZQYXJhbXMSEAoDa2V5GAEgASgJUgNrZXk=');
-
 @$core.Deprecated('Use resultDescriptor instead')
 const Result$json = {
   '1': 'Result',
diff --git a/example_protobuf/lib/proto/result.pbserver.dart b/example_protobuf/lib/proto/result.pbserver.dart
new file mode 100644
index 000000000..a26b5e08c
--- /dev/null
+++ b/example_protobuf/lib/proto/result.pbserver.dart
@@ -0,0 +1,14 @@
+//
+//  Generated code. Do not modify.
+//  source: proto/result.proto
+//
+// @dart = 2.12
+
+// ignore_for_file: annotate_overrides, camel_case_types, comment_references
+// ignore_for_file: constant_identifier_names
+// ignore_for_file: deprecated_member_use_from_same_package, library_prefixes
+// ignore_for_file: non_constant_identifier_names, prefer_final_fields
+// ignore_for_file: unnecessary_import, unnecessary_this, unused_import
+
+export 'result.pb.dart';
+
diff --git a/example_protobuf/proto/params.proto b/example_protobuf/proto/params.proto
new file mode 100644
index 000000000..45ef6e68a
--- /dev/null
+++ b/example_protobuf/proto/params.proto
@@ -0,0 +1,7 @@
+syntax = "proto3";
+
+package examples.enumerations;
+
+message Params {
+  string key = 1;
+}
\ No newline at end of file
diff --git a/example_protobuf/proto/query.proto b/example_protobuf/proto/result.proto
similarity index 60%
rename from example_protobuf/proto/query.proto
rename to example_protobuf/proto/result.proto
index 7a23c82f7..81f068105 100644
--- a/example_protobuf/proto/query.proto
+++ b/example_protobuf/proto/result.proto
@@ -1,9 +1,5 @@
 syntax = "proto3";
 
-message Params {
-  string key = 1;
-}
-
 message Result {
   string value = 1;
 }
\ No newline at end of file
diff --git a/generator/lib/src/generator.dart b/generator/lib/src/generator.dart
index 1278cbc4d..2091bfc2c 100644
--- a/generator/lib/src/generator.dart
+++ b/generator/lib/src/generator.dart
@@ -459,6 +459,17 @@ class RetrofitGenerator extends GeneratorForAnnotation<retrofit.RestApi> {
           literal(contentType.peek('mime')?.stringValue);
     }
 
+    /// gen code for request body for content-type on Protobuf body
+    final annotation = _getAnnotation(m, retrofit.Body);
+    final bodyName = annotation?.item1;
+    if (bodyName != null) {
+      if (const TypeChecker.fromRuntime(GeneratedMessage)
+          .isAssignableFromType(bodyName.type)) {
+        extraOptions[_contentType] = literal(
+            "application/x-protobuf; \${${bodyName.displayName}.info_.qualifiedMessageName == \"\" ? \"\" :\"messageType=\${${bodyName.displayName}.info_.qualifiedMessageName}\"}");
+      }
+    }
+
     extraOptions[_baseUrlVar] = refer(_baseUrlVar);
 
     final responseType = _getResponseTypeAnnotation(m);
@@ -2055,19 +2066,10 @@ ${bodyName.displayName} == null
         _typeChecker(GeneratedMessage).isAssignableFromType(returnType)) {
       headers.removeWhere(
           (key, value) => "accept".toLowerCase() == key.toLowerCase());
-      headers.addAll({"accept": literal("application/x-protobuf")});
-    }
-
-    /// gen code for request body for content-type on Protobuf body
-    final annotation = _getAnnotation(m, retrofit.Body);
-    final bodyName = annotation?.item1;
-    if (bodyName != null) {
-      if (const TypeChecker.fromRuntime(GeneratedMessage)
-          .isAssignableFromType(bodyName.type)) {
-        headers.removeWhere(
-            (key, value) => "content-type".toLowerCase() == key.toLowerCase());
-        headers.addAll({"content-type": literal("application/x-protobuf")});
-      }
+      headers.addAll({
+        "accept": literal(
+            "application/x-protobuf; \${${_displayString(returnType)}.getDefault().info_.qualifiedMessageName == \"\" ? \"\" :\"messageType=\${${_displayString(returnType)}.getDefault().info_.qualifiedMessageName}\"}")
+      });
     }
 
     return headers;
diff --git a/generator/test/src/generator_test_src.dart b/generator/test/src/generator_test_src.dart
index 312ac8c80..4b7d5cd6e 100644
--- a/generator/test/src/generator_test_src.dart
+++ b/generator/test/src/generator_test_src.dart
@@ -1940,15 +1940,16 @@ abstract class CombineBaseUrls {
   contains: true,
 )
 @ShouldGenerate(
-  '''r'accept': 'application/x-protobuf''',
-  contains: true,
-)
-@ShouldGenerate(
-  '''r'content-type': 'application/x-protobuf''',
+  '''
+      r'accept':
+          'application/x-protobuf; \${Result.getDefault().info_.qualifiedMessageName == "" ? "" : "messageType=\${Result.getDefault().info_.qualifiedMessageName}"}'
+  ''',
   contains: true,
 )
 @ShouldGenerate(
-  '''contentType: 'application/x-protobuf''',
+  '''
+      contentType:
+          'application/x-protobuf; \${params.info_.qualifiedMessageName == "" ? "" : "messageType=\${params.info_.qualifiedMessageName}"}\'''',
   contains: true,
 )
 @RestApi()
diff --git a/generator/test/src/query.pb.dart b/generator/test/src/query.pb.dart
index 0c4313161..bbab78f9f 100644
--- a/generator/test/src/query.pb.dart
+++ b/generator/test/src/query.pb.dart
@@ -1,6 +1,6 @@
 //
 //  Generated code. Do not modify.
-//  source: proto/query.proto
+//  source: proto/params.proto
 //
 // @dart = 2.12