diff --git a/src/main/scala/view/AvatarImageProvider.scala b/src/main/scala/view/AvatarImageProvider.scala
index 9425d7a..b41023f 100644
--- a/src/main/scala/view/AvatarImageProvider.scala
+++ b/src/main/scala/view/AvatarImageProvider.scala
@@ -42,9 +42,9 @@
     }
 
     if(tooltip){
-      Html(s"""<img src="${src}" class="avatar" style="width: ${size}px; height: ${size}px;" data-toggle="tooltip" title="${userName}"/>""")
+      Html(s"""<img src="${src}" class="${if(size > 20){"avatar"} else {"avatar-mini"}}" style="width: ${size}px; height: ${size}px;" data-toggle="tooltip" title="${userName}"/>""")
     } else {
-      Html(s"""<img src="${src}" class="avatar" style="width: ${size}px; height: ${size}px;" />""")
+      Html(s"""<img src="${src}" class="${if(size > 20){"avatar"} else {"avatar-mini"}}" style="width: ${size}px; height: ${size}px;" />""")
     }
   }
 
diff --git a/src/main/webapp/assets/common/css/gitbucket.css b/src/main/webapp/assets/common/css/gitbucket.css
index fae4d3b..272eae1 100644
--- a/src/main/webapp/assets/common/css/gitbucket.css
+++ b/src/main/webapp/assets/common/css/gitbucket.css
@@ -260,6 +260,12 @@
   -moz-border-radius: 4px;
 }
 
+img.avatar-mini {
+  border-radius: 2px;
+  -webkit-border-radius: 2px;
+  -moz-border-radius: 2px;
+}
+
 div.activity-message {
   margin-left: 20px;
 }