diff --git a/modules/openapi-generator/src/main/resources/php/ObjectSerializer.mustache b/modules/openapi-generator/src/main/resources/php/ObjectSerializer.mustache
index 6b27c09d5f4..20122a95505 100644
--- a/modules/openapi-generator/src/main/resources/php/ObjectSerializer.mustache
+++ b/modules/openapi-generator/src/main/resources/php/ObjectSerializer.mustache
@@ -446,6 +446,11 @@ class ObjectSerializer
             return $data;
         } else {
             $data = is_string($data) ? json_decode($data) : $data;
+
+            if (is_array($data)) {
+                $data = (object)$data;
+            }
+
             // If a discriminator is defined and points to a valid subclass, use it.
             $discriminator = $class::DISCRIMINATOR;
             if (!empty($discriminator) && isset($data->{$discriminator}) && is_string($data->{$discriminator})) {
diff --git a/samples/client/petstore/php/OpenAPIClient-php/lib/ObjectSerializer.php b/samples/client/petstore/php/OpenAPIClient-php/lib/ObjectSerializer.php
index 62756950ee2..080af144aab 100644
--- a/samples/client/petstore/php/OpenAPIClient-php/lib/ObjectSerializer.php
+++ b/samples/client/petstore/php/OpenAPIClient-php/lib/ObjectSerializer.php
@@ -455,6 +455,11 @@ class ObjectSerializer
             return $data;
         } else {
             $data = is_string($data) ? json_decode($data) : $data;
+
+            if (is_array($data)) {
+                $data = (object)$data;
+            }
+
             // If a discriminator is defined and points to a valid subclass, use it.
             $discriminator = $class::DISCRIMINATOR;
             if (!empty($discriminator) && isset($data->{$discriminator}) && is_string($data->{$discriminator})) {