diff --git a/app/assets/javascripts/diffs/components/diff_expansion_cell.vue b/app/assets/javascripts/diffs/components/diff_expansion_cell.vue
index 925385fa98a..43edc116ed1 100644
--- a/app/assets/javascripts/diffs/components/diff_expansion_cell.vue
+++ b/app/assets/javascripts/diffs/components/diff_expansion_cell.vue
@@ -223,8 +223,7 @@ export default {
         :title="__('Expand up')"
         @click="handleExpandLines(EXPAND_UP)"
       >
-        <!-- TODO: remove style & replace with correct icon, waiting for MR https://gitlab.com/gitlab-org/gitlab-design/issues/499 -->
-        <icon :size="12" name="expand-left" aria-hidden="true" style="transform: rotate(270deg);" />
+        <icon :size="12" name="expand-up" aria-hidden="true" />
       </a>
       <a class="mx-2 cursor-pointer js-unfold-all" @click="handleExpandLines()">
         <span>{{ s__('Diffs|Show all lines') }}</span>
@@ -238,8 +237,7 @@ export default {
         :title="__('Expand down')"
         @click="handleExpandLines(EXPAND_DOWN)"
       >
-        <!-- TODO: remove style & replace with correct icon, waiting for MR https://gitlab.com/gitlab-org/gitlab-design/issues/499 -->
-        <icon :size="12" name="expand-left" aria-hidden="true" style="transform: rotate(90deg);" />
+        <icon :size="12" name="expand-down" aria-hidden="true" />
       </a>
     </div>
   </td>
diff --git a/changelogs/unreleased/66161-replace-expand-icons.yml b/changelogs/unreleased/66161-replace-expand-icons.yml
new file mode 100644
index 00000000000..e28e01108a8
--- /dev/null
+++ b/changelogs/unreleased/66161-replace-expand-icons.yml
@@ -0,0 +1,5 @@
+---
+title: Replaced expand diff icons
+merge_request: 31907
+author:
+type: changed