diff --git a/modules/swagger-codegen/src/main/resources/csharp/api_test.mustache b/modules/swagger-codegen/src/main/resources/csharp/api_test.mustache
index 3afe27063dd..2e638711b0f 100644
--- a/modules/swagger-codegen/src/main/resources/csharp/api_test.mustache
+++ b/modules/swagger-codegen/src/main/resources/csharp/api_test.mustache
@@ -54,6 +54,10 @@ namespace {{packageName}}.Test
         public void {{operationId}}Test()
         {
             // TODO: add unit test for the method '{{operationId}}'
+            {{#allParams}}{{{dataType}}} {{paramName}} = null; // TODO: replace null with proper value
+            {{/allParams}}
+            {{#returnType}}var response = {{/returnType}}instance.{{operationId}}({{#allParams}}{{paramName}}{{#hasMore}}, {{/hasMore}}{{/allParams}});
+            {{#returnType}}Assert.IsInstanceOf<{{{returnType}}}> (response, "response is {{{returnType}}}");{{/returnType}} 
         }
         {{/operation}}{{/operations}}
     }
diff --git a/samples/client/petstore/csharp/SwaggerClientTest/Lib/SwaggerClient.Test/PetApiTests.cs b/samples/client/petstore/csharp/SwaggerClientTest/Lib/SwaggerClient.Test/PetApiTests.cs
index aeb2f1262b9..a7caec2f54c 100644
--- a/samples/client/petstore/csharp/SwaggerClientTest/Lib/SwaggerClient.Test/PetApiTests.cs
+++ b/samples/client/petstore/csharp/SwaggerClientTest/Lib/SwaggerClient.Test/PetApiTests.cs
@@ -53,6 +53,10 @@ namespace IO.Swagger.Test
         public void UpdatePetTest()
         {
             // TODO: add unit test for the method 'UpdatePet'
+            Pet body = null; // TODO: replace null with proper value
+            
+            instance.UpdatePet(body);
+             
         }
         
         /// <summary>
@@ -62,6 +66,10 @@ namespace IO.Swagger.Test
         public void AddPetTest()
         {
             // TODO: add unit test for the method 'AddPet'
+            Pet body = null; // TODO: replace null with proper value
+            
+            instance.AddPet(body);
+             
         }
         
         /// <summary>
@@ -71,6 +79,10 @@ namespace IO.Swagger.Test
         public void FindPetsByStatusTest()
         {
             // TODO: add unit test for the method 'FindPetsByStatus'
+            List<string> status = null; // TODO: replace null with proper value
+            
+            var response = instance.FindPetsByStatus(status);
+            Assert.IsInstanceOf<List<Pet>> (response, "response is List<Pet>"); 
         }
         
         /// <summary>
@@ -80,6 +92,10 @@ namespace IO.Swagger.Test
         public void FindPetsByTagsTest()
         {
             // TODO: add unit test for the method 'FindPetsByTags'
+            List<string> tags = null; // TODO: replace null with proper value
+            
+            var response = instance.FindPetsByTags(tags);
+            Assert.IsInstanceOf<List<Pet>> (response, "response is List<Pet>"); 
         }
         
         /// <summary>
@@ -89,6 +105,10 @@ namespace IO.Swagger.Test
         public void GetPetByIdTest()
         {
             // TODO: add unit test for the method 'GetPetById'
+            long? petId = null; // TODO: replace null with proper value
+            
+            var response = instance.GetPetById(petId);
+            Assert.IsInstanceOf<Pet> (response, "response is Pet"); 
         }
         
         /// <summary>
@@ -98,6 +118,12 @@ namespace IO.Swagger.Test
         public void UpdatePetWithFormTest()
         {
             // TODO: add unit test for the method 'UpdatePetWithForm'
+            string petId = null; // TODO: replace null with proper value
+            string name = null; // TODO: replace null with proper value
+            string status = null; // TODO: replace null with proper value
+            
+            instance.UpdatePetWithForm(petId, name, status);
+             
         }
         
         /// <summary>
@@ -107,6 +133,11 @@ namespace IO.Swagger.Test
         public void DeletePetTest()
         {
             // TODO: add unit test for the method 'DeletePet'
+            long? petId = null; // TODO: replace null with proper value
+            string apiKey = null; // TODO: replace null with proper value
+            
+            instance.DeletePet(petId, apiKey);
+             
         }
         
         /// <summary>
@@ -116,6 +147,12 @@ namespace IO.Swagger.Test
         public void UploadFileTest()
         {
             // TODO: add unit test for the method 'UploadFile'
+            long? petId = null; // TODO: replace null with proper value
+            string additionalMetadata = null; // TODO: replace null with proper value
+            Stream file = null; // TODO: replace null with proper value
+            
+            instance.UploadFile(petId, additionalMetadata, file);
+             
         }
         
         /// <summary>
@@ -125,6 +162,10 @@ namespace IO.Swagger.Test
         public void GetPetByIdWithByteArrayTest()
         {
             // TODO: add unit test for the method 'GetPetByIdWithByteArray'
+            long? petId = null; // TODO: replace null with proper value
+            
+            var response = instance.GetPetByIdWithByteArray(petId);
+            Assert.IsInstanceOf<byte[]> (response, "response is byte[]"); 
         }
         
         /// <summary>
@@ -134,6 +175,10 @@ namespace IO.Swagger.Test
         public void AddPetUsingByteArrayTest()
         {
             // TODO: add unit test for the method 'AddPetUsingByteArray'
+            byte[] body = null; // TODO: replace null with proper value
+            
+            instance.AddPetUsingByteArray(body);
+             
         }
         
     }
diff --git a/samples/client/petstore/csharp/SwaggerClientTest/Lib/SwaggerClient.Test/StoreApiTests.cs b/samples/client/petstore/csharp/SwaggerClientTest/Lib/SwaggerClient.Test/StoreApiTests.cs
index f271564e62b..8e3f99eff2d 100644
--- a/samples/client/petstore/csharp/SwaggerClientTest/Lib/SwaggerClient.Test/StoreApiTests.cs
+++ b/samples/client/petstore/csharp/SwaggerClientTest/Lib/SwaggerClient.Test/StoreApiTests.cs
@@ -53,6 +53,9 @@ namespace IO.Swagger.Test
         public void GetInventoryTest()
         {
             // TODO: add unit test for the method 'GetInventory'
+            
+            var response = instance.GetInventory();
+            Assert.IsInstanceOf<Dictionary<string, int?>> (response, "response is Dictionary<string, int?>"); 
         }
         
         /// <summary>
@@ -62,6 +65,10 @@ namespace IO.Swagger.Test
         public void PlaceOrderTest()
         {
             // TODO: add unit test for the method 'PlaceOrder'
+            Order body = null; // TODO: replace null with proper value
+            
+            var response = instance.PlaceOrder(body);
+            Assert.IsInstanceOf<Order> (response, "response is Order"); 
         }
         
         /// <summary>
@@ -71,6 +78,10 @@ namespace IO.Swagger.Test
         public void GetOrderByIdTest()
         {
             // TODO: add unit test for the method 'GetOrderById'
+            string orderId = null; // TODO: replace null with proper value
+            
+            var response = instance.GetOrderById(orderId);
+            Assert.IsInstanceOf<Order> (response, "response is Order"); 
         }
         
         /// <summary>
@@ -80,6 +91,10 @@ namespace IO.Swagger.Test
         public void DeleteOrderTest()
         {
             // TODO: add unit test for the method 'DeleteOrder'
+            string orderId = null; // TODO: replace null with proper value
+            
+            instance.DeleteOrder(orderId);
+             
         }
         
     }
diff --git a/samples/client/petstore/csharp/SwaggerClientTest/Lib/SwaggerClient.Test/UserApiTests.cs b/samples/client/petstore/csharp/SwaggerClientTest/Lib/SwaggerClient.Test/UserApiTests.cs
index 13d62345eb9..0d543c384aa 100644
--- a/samples/client/petstore/csharp/SwaggerClientTest/Lib/SwaggerClient.Test/UserApiTests.cs
+++ b/samples/client/petstore/csharp/SwaggerClientTest/Lib/SwaggerClient.Test/UserApiTests.cs
@@ -53,6 +53,10 @@ namespace IO.Swagger.Test
         public void CreateUserTest()
         {
             // TODO: add unit test for the method 'CreateUser'
+            User body = null; // TODO: replace null with proper value
+            
+            instance.CreateUser(body);
+             
         }
         
         /// <summary>
@@ -62,6 +66,10 @@ namespace IO.Swagger.Test
         public void CreateUsersWithArrayInputTest()
         {
             // TODO: add unit test for the method 'CreateUsersWithArrayInput'
+            List<User> body = null; // TODO: replace null with proper value
+            
+            instance.CreateUsersWithArrayInput(body);
+             
         }
         
         /// <summary>
@@ -71,6 +79,10 @@ namespace IO.Swagger.Test
         public void CreateUsersWithListInputTest()
         {
             // TODO: add unit test for the method 'CreateUsersWithListInput'
+            List<User> body = null; // TODO: replace null with proper value
+            
+            instance.CreateUsersWithListInput(body);
+             
         }
         
         /// <summary>
@@ -80,6 +92,11 @@ namespace IO.Swagger.Test
         public void LoginUserTest()
         {
             // TODO: add unit test for the method 'LoginUser'
+            string username = null; // TODO: replace null with proper value
+            string password = null; // TODO: replace null with proper value
+            
+            var response = instance.LoginUser(username, password);
+            Assert.IsInstanceOf<string> (response, "response is string"); 
         }
         
         /// <summary>
@@ -89,6 +106,9 @@ namespace IO.Swagger.Test
         public void LogoutUserTest()
         {
             // TODO: add unit test for the method 'LogoutUser'
+            
+            instance.LogoutUser();
+             
         }
         
         /// <summary>
@@ -98,6 +118,10 @@ namespace IO.Swagger.Test
         public void GetUserByNameTest()
         {
             // TODO: add unit test for the method 'GetUserByName'
+            string username = null; // TODO: replace null with proper value
+            
+            var response = instance.GetUserByName(username);
+            Assert.IsInstanceOf<User> (response, "response is User"); 
         }
         
         /// <summary>
@@ -107,6 +131,11 @@ namespace IO.Swagger.Test
         public void UpdateUserTest()
         {
             // TODO: add unit test for the method 'UpdateUser'
+            string username = null; // TODO: replace null with proper value
+            User body = null; // TODO: replace null with proper value
+            
+            instance.UpdateUser(username, body);
+             
         }
         
         /// <summary>
@@ -116,6 +145,10 @@ namespace IO.Swagger.Test
         public void DeleteUserTest()
         {
             // TODO: add unit test for the method 'DeleteUser'
+            string username = null; // TODO: replace null with proper value
+            
+            instance.DeleteUser(username);
+             
         }
         
     }