diff --git a/modules/openapi-generator/src/main/resources/php/api.mustache b/modules/openapi-generator/src/main/resources/php/api.mustache
index ccae14d1424b..7d25f0d82d4e 100644
--- a/modules/openapi-generator/src/main/resources/php/api.mustache
+++ b/modules/openapi-generator/src/main/resources/php/api.mustache
@@ -654,7 +654,7 @@ use {{invokerPackage}}\ObjectSerializer;
 
         $formData = $formDataProcessor->prepare([
         {{/-first}}
-            '{{paramName}}' => ${{paramName}},
+            '{{baseName}}' => ${{paramName}},
         {{#-last}}
         ]);
 
diff --git a/samples/client/petstore/php/OpenAPIClient-php/lib/Api/FakeApi.php b/samples/client/petstore/php/OpenAPIClient-php/lib/Api/FakeApi.php
index 3c4833213fde..41ae26b81611 100644
--- a/samples/client/petstore/php/OpenAPIClient-php/lib/Api/FakeApi.php
+++ b/samples/client/petstore/php/OpenAPIClient-php/lib/Api/FakeApi.php
@@ -5647,7 +5647,7 @@ public function testEndpointParametersRequest($number, $double, $pattern_without
             'byte' => $byte,
             'binary' => $binary,
             'date' => $date,
-            'date_time' => $date_time,
+            'dateTime' => $date_time,
             'password' => $password,
             'callback' => $callback,
         ]);
diff --git a/samples/client/petstore/php/OpenAPIClient-php/lib/Api/PetApi.php b/samples/client/petstore/php/OpenAPIClient-php/lib/Api/PetApi.php
index 5afbdb9c3777..0e75b91decb8 100644
--- a/samples/client/petstore/php/OpenAPIClient-php/lib/Api/PetApi.php
+++ b/samples/client/petstore/php/OpenAPIClient-php/lib/Api/PetApi.php
@@ -2431,7 +2431,7 @@ public function uploadFileRequest($pet_id, $additional_metadata = null, $file =
         $formDataProcessor = new FormDataProcessor();
 
         $formData = $formDataProcessor->prepare([
-            'additional_metadata' => $additional_metadata,
+            'additionalMetadata' => $additional_metadata,
             'file' => $file,
         ]);
 
@@ -2732,8 +2732,8 @@ public function uploadFileWithRequiredFileRequest($pet_id, $required_file, $addi
         $formDataProcessor = new FormDataProcessor();
 
         $formData = $formDataProcessor->prepare([
-            'additional_metadata' => $additional_metadata,
-            'required_file' => $required_file,
+            'additionalMetadata' => $additional_metadata,
+            'requiredFile' => $required_file,
         ]);
 
         $formParams = $formDataProcessor->flatten($formData);
@@ -3078,7 +3078,7 @@ public function uploadImageFullFormDataRequest($pet_id, $name, $photo_urls, $id
             'id' => $id,
             'category' => $category,
             'name' => $name,
-            'photo_urls' => $photo_urls,
+            'photoUrls' => $photo_urls,
             'tags' => $tags,
             'status' => $status,
             'file' => $file,
diff --git a/samples/client/petstore/php/OpenAPIClient-php/tests/PetApiTest.php b/samples/client/petstore/php/OpenAPIClient-php/tests/PetApiTest.php
index eb32525895b3..dbb25e8e3c4f 100644
--- a/samples/client/petstore/php/OpenAPIClient-php/tests/PetApiTest.php
+++ b/samples/client/petstore/php/OpenAPIClient-php/tests/PetApiTest.php
@@ -414,8 +414,8 @@ public function testObjectInFormData()
         $contents = $request->getBody()->getContents();
 
         $this->assertBodyContents('name', $name, $contents);
-        $this->assertBodyContents('photo_urls[0]', $photo_urls[0], $contents);
-        $this->assertBodyContents('photo_urls[1]', $photo_urls[1], $contents);
+        $this->assertBodyContents('photoUrls[0]', $photo_urls[0], $contents);
+        $this->assertBodyContents('photoUrls[1]', $photo_urls[1], $contents);
         $this->assertBodyContents('category[id]', $category->getId(), $contents);
         $this->assertBodyContents('category[name]', $category->getName(), $contents);
         $this->assertBodyContents('tags[0][id]', $tags[0]->getId(), $contents);