diff --git a/src/ol/format/WFS.js b/src/ol/format/WFS.js
index 1480b43fe9..e3cd863db2 100644
--- a/src/ol/format/WFS.js
+++ b/src/ol/format/WFS.js
@@ -408,7 +408,7 @@ class WFS extends XMLFeature {
         node.setAttribute('count', String(options.count));
       }
       if (options.viewParams !== undefined) {
-        node.setAttribute('viewParams ', options.viewParams);
+        node.setAttribute('viewParams', options.viewParams);
       }
       filter = options.filter;
       if (options.bbox) {