diff --git a/models/issue.go b/models/issue.go
index a7392633a..b903e82ad 100644
--- a/models/issue.go
+++ b/models/issue.go
@@ -745,11 +745,11 @@ func AddDeletePRBranchComment(doer *User, repo *Repository, issueID int64, branc
 		return err
 	}
 	var opts = &CreateCommentOptions{
-		Type:      CommentTypeDeleteBranch,
-		Doer:      doer,
-		Repo:      repo,
-		Issue:     issue,
-		CommitSHA: branchName,
+		Type:   CommentTypeDeleteBranch,
+		Doer:   doer,
+		Repo:   repo,
+		Issue:  issue,
+		OldRef: branchName,
 	}
 	if _, err = createComment(sess, opts); err != nil {
 		return err
diff --git a/models/migrations/migrations.go b/models/migrations/migrations.go
index c1a3b186c..c926ee6cc 100644
--- a/models/migrations/migrations.go
+++ b/models/migrations/migrations.go
@@ -284,6 +284,8 @@ var migrations = []Migration{
 	NewMigration("Add user redirect", addUserRedirect),
 	// v168 -> v169
 	NewMigration("Recreate user table to fix default values", recreateUserTableToFixDefaultValues),
+	// v169 -> v170
+	NewMigration("Update DeleteBranch comments to set the old_ref to the commit_sha", commentTypeDeleteBranchUseOldRef),
 }
 
 // GetCurrentDBVersion returns the current db version
diff --git a/models/migrations/v169.go b/models/migrations/v169.go
new file mode 100644
index 000000000..e976281c5
--- /dev/null
+++ b/models/migrations/v169.go
@@ -0,0 +1,14 @@
+// Copyright 2021 The Gitea Authors. All rights reserved.
+// Use of this source code is governed by a MIT-style
+// license that can be found in the LICENSE file.
+
+package migrations
+
+import (
+	"xorm.io/xorm"
+)
+
+func commentTypeDeleteBranchUseOldRef(x *xorm.Engine) error {
+	_, err := x.Exec("UPDATE comment SET old_ref = commit_sha, commit_sha = '' WHERE type = 11")
+	return err
+}
diff --git a/templates/repo/issue/view_content/comments.tmpl b/templates/repo/issue/view_content/comments.tmpl
index abf5792a9..63fe73857 100644
--- a/templates/repo/issue/view_content/comments.tmpl
+++ b/templates/repo/issue/view_content/comments.tmpl
@@ -251,7 +251,7 @@
 			</a>
 			<span class="text grey">
 				<a class="author" href="{{.Poster.HomeLink}}">{{.Poster.GetDisplayName}}</a>
-				{{$.i18n.Tr "repo.issues.delete_branch_at" (.CommitSHA|Escape) $createdStr | Safe}}
+				{{$.i18n.Tr "repo.issues.delete_branch_at" (.OldRef|Escape) $createdStr | Safe}}
 			</span>
 		</div>
 	{{else if eq .Type 12}}