diff --git a/models/git_diff.go b/models/git_diff.go
index f72e8e1b3..44027bec6 100644
--- a/models/git_diff.go
+++ b/models/git_diff.go
@@ -67,6 +67,10 @@ func (d *DiffLine) GetType() int {
 	return int(d.Type)
 }
 
+func (d *DiffLine) CanComment() bool {
+	return len(d.Comments) == 0 && d.Type != DiffLineSection
+}
+
 // GetCommentSide returns the comment side of the first comment, if not set returns empty string
 func (d *DiffLine) GetCommentSide() string {
 	if len(d.Comments) == 0 {
diff --git a/templates/repo/diff/box.tmpl b/templates/repo/diff/box.tmpl
index 39a66a734..77a0e955e 100644
--- a/templates/repo/diff/box.tmpl
+++ b/templates/repo/diff/box.tmpl
@@ -106,7 +106,7 @@
 
 														</td>
 														<td class="lines-code lines-code-old halfwidth">
-															{{if and $.SignedUserID (not (len $line.Comments))}}
+															{{if and $.root.SignedUserID $line.CanComment}}
 																<a class="ui green button add-code-comment add-code-comment-left" data-path="{{$file.Name}}" data-side="left" data-idx="{{$line.LeftIdx}}">+</a>
 															{{end}}
 															<pre><code class="wrap {{if $highlightClass}}language-{{$highlightClass}}{{else}}nohighlight{{end}}">{{if $line.LeftIdx}}{{$section.GetComputedInlineDiffFor $line}}{{end}}</code></pre>
@@ -116,7 +116,7 @@
 														</td>
 
 														<td class="lines-code lines-code-new halfwidth">
-															{{if and $.SignedUserID (not (len $line.Comments))}}
+															{{if and $.root.SignedUserID $line.CanComment}}
 																<a class="ui green button add-code-comment add-code-comment-right" data-path="{{$file.Name}}" data-side="right" data-idx="{{$line.RightIdx}}">+</a>
 															{{end}}
 															<pre><code class="wrap {{if $highlightClass}}language-{{$highlightClass}}{{else}}nohighlight{{end}}">{{if $line.RightIdx}}{{$section.GetComputedInlineDiffFor $line}}{{end}}</code></pre>
diff --git a/templates/repo/diff/section_unified.tmpl b/templates/repo/diff/section_unified.tmpl
index f089df4c2..491572cde 100644
--- a/templates/repo/diff/section_unified.tmpl
+++ b/templates/repo/diff/section_unified.tmpl
@@ -16,7 +16,7 @@
 			</td>
 			{{end}}
 			<td class="lines-code {{if (not $line.RightIdx)}}lines-code-old{{end}}">
-				{{if and $.root.SignedUserID (not (len $line.Comments))}}
+				{{if and $.root.SignedUserID $line.CanComment}}
 					<a class="ui green button add-code-comment add-code-comment-{{if $line.RightIdx}}right{{else}}left{{end}}" data-path="{{$file.Name}}" data-side="{{if $line.RightIdx}}right{{else}}left{{end}}" data-idx="{{if $line.RightIdx}}{{$line.RightIdx}}{{else}}{{$line.LeftIdx}}{{end}}">+</a>
 				{{end}}
 				<pre><code class="wrap {{if $highlightClass}}language-{{$highlightClass}}{{else}}nohighlight{{end}}">{{$section.GetComputedInlineDiffFor $line}}</code></pre>