diff --git a/templates/base/http-clients/fetch-http-client.ejs b/templates/base/http-clients/fetch-http-client.ejs
index a1db3833..a64d2432 100644
--- a/templates/base/http-clients/fetch-http-client.ejs
+++ b/templates/base/http-clients/fetch-http-client.ejs
@@ -80,20 +80,22 @@ export class HttpClient<SecurityDataType = unknown> {
     }
 
     protected addArrayQueryParam(query: QueryParamsType, key: string) {
-        const value = query[key];
-        return value.map((v: any) => this.encodeQueryParam(key, v)).join("&");
+        const value = Array.isArray(query[key])
+            ? query[key].map((value, index) => [index, value])
+            : Object.entries(query[key]);
+        return value.map(([arrayKey, value]: any) => this.encodeQueryParam(`${key}[${arrayKey}]`, value)).join("&");
     }
 
     protected toQueryString(rawQuery?: QueryParamsType): string {
         const query = rawQuery || {};
         const keys = Object.keys(query).filter((key) => "undefined" !== typeof query[key]);
         return keys
-                .map((key) =>
-                    Array.isArray(query[key])
-                    ? this.addArrayQueryParam(query, key)
-                    : this.addQueryParam(query, key),
-                )
-                .join("&");
+        .map((key) =>
+            typeof query[key] === "object" || Array.isArray(query[key])
+            ? this.addArrayQueryParam(query, key)
+            : this.addQueryParam(query, key),
+        )
+        .join("&");
     }
 
     protected addQueryParams(rawQuery?: QueryParamsType): string {