diff --git a/modules/swagger-codegen/src/main/resources/php/ObjectSerializer.mustache b/modules/swagger-codegen/src/main/resources/php/ObjectSerializer.mustache
index f07a4d18cc0a..460b69b705bb 100644
--- a/modules/swagger-codegen/src/main/resources/php/ObjectSerializer.mustache
+++ b/modules/swagger-codegen/src/main/resources/php/ObjectSerializer.mustache
@@ -261,7 +261,7 @@ class ObjectSerializer
             // determine file name
             if (array_key_exists('Content-Disposition', $httpHeaders) &&
                 preg_match('/inline; filename=[\'"]?([^\'"\s]+)[\'"]?$/i', $httpHeaders['Content-Disposition'], $match)) {
-                $filename = Configuration::getDefaultConfiguration()->getTempFolderPath() . self::sanitizeFilename($match[1]);
+                $filename = Configuration::getDefaultConfiguration()->getTempFolderPath() . DIRECTORY_SEPARATOR . self::sanitizeFilename($match[1]);
             } else {
                 $filename = tempnam(Configuration::getDefaultConfiguration()->getTempFolderPath(), '');
             }
diff --git a/samples/client/petstore/php/SwaggerClient-php/lib/ObjectSerializer.php b/samples/client/petstore/php/SwaggerClient-php/lib/ObjectSerializer.php
index 1f7e3f3d6148..6a4225ff5d5a 100644
--- a/samples/client/petstore/php/SwaggerClient-php/lib/ObjectSerializer.php
+++ b/samples/client/petstore/php/SwaggerClient-php/lib/ObjectSerializer.php
@@ -271,7 +271,7 @@ public static function deserialize($data, $class, $httpHeaders = null)
             // determine file name
             if (array_key_exists('Content-Disposition', $httpHeaders) &&
                 preg_match('/inline; filename=[\'"]?([^\'"\s]+)[\'"]?$/i', $httpHeaders['Content-Disposition'], $match)) {
-                $filename = Configuration::getDefaultConfiguration()->getTempFolderPath() . self::sanitizeFilename($match[1]);
+                $filename = Configuration::getDefaultConfiguration()->getTempFolderPath() . DIRECTORY_SEPARATOR . self::sanitizeFilename($match[1]);
             } else {
                 $filename = tempnam(Configuration::getDefaultConfiguration()->getTempFolderPath(), '');
             }
diff --git a/samples/client/petstore/php/SwaggerClient-php/phpunit.xml.dist b/samples/client/petstore/php/SwaggerClient-php/phpunit.xml.dist
index c12ee1484773..cadedbc24690 100644
--- a/samples/client/petstore/php/SwaggerClient-php/phpunit.xml.dist
+++ b/samples/client/petstore/php/SwaggerClient-php/phpunit.xml.dist
@@ -14,8 +14,8 @@
 
     <filter>
         <whitelist processUncoveredFilesFromWhitelist="true">
-            <directory suffix=".php">./lib/Api</directory>
-            <directory suffix=".php">./lib/Model</directory>
+            <directory suffix=".php">./lib\Api</directory>
+            <directory suffix=".php">./lib\Model</directory>
         </whitelist>
     </filter>
 </phpunit>