diff --git a/modules/openapi-generator/src/main/resources/C-libcurl/object-body.mustache b/modules/openapi-generator/src/main/resources/C-libcurl/object-body.mustache
index 9606d41d980..ff293bcdac8 100644
--- a/modules/openapi-generator/src/main/resources/C-libcurl/object-body.mustache
+++ b/modules/openapi-generator/src/main/resources/C-libcurl/object-body.mustache
@@ -28,7 +28,7 @@ cJSON *object_convertToJSON(object_t *object) {
     }
 
     if (!object->temporary) {
-        return cJSON_Parse("{}");
+        return cJSON_Parse("null");
     }
 
     return cJSON_Parse(object->temporary);
diff --git a/samples/client/petstore/c/model/object.c b/samples/client/petstore/c/model/object.c
index 9606d41d980..ff293bcdac8 100644
--- a/samples/client/petstore/c/model/object.c
+++ b/samples/client/petstore/c/model/object.c
@@ -28,7 +28,7 @@ cJSON *object_convertToJSON(object_t *object) {
     }
 
     if (!object->temporary) {
-        return cJSON_Parse("{}");
+        return cJSON_Parse("null");
     }
 
     return cJSON_Parse(object->temporary);