diff --git a/app/assets/javascripts/discourse/views/topic-list-item.js.es6 b/app/assets/javascripts/discourse/views/topic-list-item.js.es6
index 960dadbe01f..c3afd0cce5a 100644
--- a/app/assets/javascripts/discourse/views/topic-list-item.js.es6
+++ b/app/assets/javascripts/discourse/views/topic-list-item.js.es6
@@ -13,6 +13,10 @@ export default Discourse.View.extend(StringBuffer, {
     var classes = [];
     var topic = this.get('topic');
 
+    if (topic.get('category')) {
+      classes.push("category-" + topic.get('category.slug'));
+    }
+
     if(topic.get('hasExcerpt')){
       classes.push('has-excerpt');
     }