diff --git a/lib/api/api-router.js b/lib/api/api-router.js
index 142c3eba..ea38b88c 100644
--- a/lib/api/api-router.js
+++ b/lib/api/api-router.js
@@ -86,11 +86,15 @@ module.exports = class ApiRouter {
         const windshaftLogger = environmentOptions.log_windshaft && global.log4js ?
                                 global.log4js.getLogger('[windshaft]') :
                                 null;
-        const mapStore = new windshaft.storage.MapStore({
+
+        const mapStoreOptions = {
             pool: redisPool,
-            expire_time: serverOptions.grainstore.default_layergroup_ttl,
             logger: windshaftLogger
-        });
+        };
+        if (Number.isFinite(serverOptions.grainstore.default_layergroup_ttl)) {
+            mapStoreOptions.expire_time = serverOptions.grainstore.default_layergroup_ttl;
+        }
+        const mapStore = new windshaft.storage.MapStore(mapStoreOptions);
 
         const rendererFactory = createRendererFactory({ redisPool, serverOptions, environmentOptions });