diff --git a/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/TypeScriptFetchClientCodegen.java b/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/TypeScriptFetchClientCodegen.java
index c5b857ef2cd9..eec358455da5 100644
--- a/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/TypeScriptFetchClientCodegen.java
+++ b/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/TypeScriptFetchClientCodegen.java
@@ -247,23 +247,9 @@ public Map<String, Object> postProcessOperationsWithModels(Map<String, Object> o
         this.addOperationObjectResponseInformation(operations);
         this.addOperationPrefixParameterInterfacesInformation(operations);
         this.escapeOperationIds(operations);
-        this.addDeepObjectVendorExtension(operations);
         return operations;
     }
 
-    private void addDeepObjectVendorExtension(Map<String, Object> operations) {
-        Map<String, Object> _operations = (Map<String, Object>) operations.get("operations");
-        List<CodegenOperation> operationList = (List<CodegenOperation>) _operations.get("operation");
-
-        for (CodegenOperation op : operationList) {
-            for (CodegenParameter param : op.queryParams) {
-                if (param.style != null && param.style.equals("deepObject")) {
-                    param.vendorExtensions.put("x-codegen-isDeepObject", true);
-                }
-            }
-        }
-    }
-
     private void escapeOperationIds(Map<String, Object> operations) {
         Map<String, Object> _operations = (Map<String, Object>) operations.get("operations");
         List<CodegenOperation> operationList = (List<CodegenOperation>) _operations.get("operation");
diff --git a/modules/openapi-generator/src/main/resources/typescript-fetch/apis.mustache b/modules/openapi-generator/src/main/resources/typescript-fetch/apis.mustache
index be03f0eb1771..056e0dbb2677 100644
--- a/modules/openapi-generator/src/main/resources/typescript-fetch/apis.mustache
+++ b/modules/openapi-generator/src/main/resources/typescript-fetch/apis.mustache
@@ -122,12 +122,7 @@ export class {{classname}} extends runtime.BaseAPI {
             queryParameters['{{baseName}}'] = (requestParameters.{{paramName}} as any).toISOString().substr(0,10);
             {{/isDate}}
             {{^isDate}}
-            {{#vendorExtensions.x-codegen-isDeepObject}}
-            queryParameters['{{baseName}}'] = runtime.querystring(requestParameters.{{paramName}} as unknown as runtime.HTTPQuery, '{{baseName}}');
-            {{/vendorExtensions.x-codegen-isDeepObject}}
-            {{^vendorExtensions.x-codegen-isDeepObject}}
             queryParameters['{{baseName}}'] = requestParameters.{{paramName}};
-            {{/vendorExtensions.x-codegen-isDeepObject}}
             {{/isDate}}
             {{/isDateTime}}
         }