diff --git a/app/assets/javascripts/vue_shared/components/markdown/toolbar.vue b/app/assets/javascripts/vue_shared/components/markdown/toolbar.vue
index 3b57b5e8da4..d6c398c8946 100644
--- a/app/assets/javascripts/vue_shared/components/markdown/toolbar.vue
+++ b/app/assets/javascripts/vue_shared/components/markdown/toolbar.vue
@@ -33,37 +33,36 @@ export default {
   <div class="comment-toolbar clearfix">
     <div class="toolbar-text">
       <template v-if="!hasQuickActionsDocsPath && markdownDocsPath">
-        <gl-link :href="markdownDocsPath" target="_blank" tabindex="-1">
-          Markdown is supported
-        </gl-link>
+        <gl-link :href="markdownDocsPath" target="_blank" tabindex="-1"
+          >Markdown is supported</gl-link
+        >
       </template>
       <template v-if="hasQuickActionsDocsPath && markdownDocsPath">
-        <gl-link :href="markdownDocsPath" target="_blank" tabindex="-1"> Markdown </gl-link>
-        and
-        <gl-link :href="quickActionsDocsPath" target="_blank" tabindex="-1">
-          quick actions
-        </gl-link>
+        <gl-link :href="markdownDocsPath" target="_blank" tabindex="-1">Markdown</gl-link> and
+        <gl-link :href="quickActionsDocsPath" target="_blank" tabindex="-1">quick actions</gl-link>
         are supported
       </template>
     </div>
     <span v-if="canAttachFile" class="uploading-container">
       <span class="uploading-progress-container hide">
-        <i class="fa fa-file-image-o toolbar-button-icon" aria-hidden="true"> </i>
-        <span class="attaching-file-message"></span> <span class="uploading-progress">0%</span>
+        <i class="fa fa-file-image-o toolbar-button-icon" aria-hidden="true"></i>
+        <span class="attaching-file-message"></span>
+        <span class="uploading-progress">0%</span>
         <span class="uploading-spinner">
-          <i class="fa fa-spinner fa-spin toolbar-button-icon" aria-hidden="true"> </i>
+          <i class="fa fa-spinner fa-spin toolbar-button-icon" aria-hidden="true"></i>
         </span>
       </span>
       <span class="uploading-error-container hide">
         <span class="uploading-error-icon">
-          <i class="fa fa-file-image-o toolbar-button-icon" aria-hidden="true"> </i>
+          <i class="fa fa-file-image-o toolbar-button-icon" aria-hidden="true"></i>
         </span>
         <span class="uploading-error-message"></span>
         <button class="retry-uploading-link" type="button">Try again</button> or
         <button class="attach-new-file markdown-selector" type="button">attach a new file</button>
       </span>
-      <button class="markdown-selector button-attach-file" tabindex="-1" type="button">
-        <i class="fa fa-file-image-o toolbar-button-icon" aria-hidden="true"> </i> Attach a file
+      <button class="markdown-selector button-attach-file btn-link" tabindex="-1" type="button">
+        <i class="fa fa-file-image-o toolbar-button-icon" aria-hidden="true"></i
+        ><span class="text-attach-file">Attach a file</span>
       </button>
       <button class="btn btn-default btn-sm hide button-cancel-uploading-files" type="button">
         Cancel
diff --git a/app/assets/stylesheets/pages/note_form.scss b/app/assets/stylesheets/pages/note_form.scss
index 3343b55d24b..8c7b124dd33 100644
--- a/app/assets/stylesheets/pages/note_form.scss
+++ b/app/assets/stylesheets/pages/note_form.scss
@@ -334,7 +334,7 @@ table {
 .toolbar-button-icon {
   position: relative;
   top: 1px;
-  margin-right: 3px;
+  margin-right: $gl-padding-4;
   color: inherit;
   font-size: 16px;
 }
@@ -461,6 +461,15 @@ table {
   border: 0;
   font-size: 14px;
   line-height: 16px;
+
+  &:hover,
+  &:focus {
+    text-decoration: none;
+
+    .text-attach-file {
+      text-decoration: underline;
+    }
+  }
 }
 
 .markdown-selector {
diff --git a/app/views/shared/notes/_hints.html.haml b/app/views/shared/notes/_hints.html.haml
index 46f3f8428f1..fae7d6526e8 100644
--- a/app/views/shared/notes/_hints.html.haml
+++ b/app/views/shared/notes/_hints.html.haml
@@ -28,8 +28,9 @@
       or
       %button.attach-new-file.markdown-selector{ type: 'button' }= _("attach a new file")
 
-    %button.markdown-selector.button-attach-file{ type: 'button', tabindex: '-1' }
+    %button.markdown-selector.button-attach-file.btn-link{ type: 'button', tabindex: '-1' }
       = icon('file-image-o', class: 'toolbar-button-icon')
-      = _("Attach a file")
+      %span.text-attach-file<>
+        = _("Attach a file")
 
     %button.btn.btn-default.btn-sm.hide.button-cancel-uploading-files{ type: 'button' }= _("Cancel")
diff --git a/changelogs/unreleased/61339-Add-underline-to-attach-a-file.yml b/changelogs/unreleased/61339-Add-underline-to-attach-a-file.yml
new file mode 100644
index 00000000000..c3808709fca
--- /dev/null
+++ b/changelogs/unreleased/61339-Add-underline-to-attach-a-file.yml
@@ -0,0 +1,5 @@
+---
+title: Add hover and focus to Attach a file
+merge_request: 28682
+author: Marcel van Remmerden
+type: fixed