diff --git a/templates/repo/issue/view_content/sidebar.tmpl b/templates/repo/issue/view_content/sidebar.tmpl
index 3fcefcb417252..7c23535215663 100644
--- a/templates/repo/issue/view_content/sidebar.tmpl
+++ b/templates/repo/issue/view_content/sidebar.tmpl
@@ -362,7 +362,7 @@
 				<div class="gt-df gt-sb gt-ac">
 					<div class="due-date {{if .Issue.IsOverdue}}text red{{end}}" {{if .Issue.IsOverdue}}data-tooltip-content="{{.locale.Tr "repo.issues.due_date_overdue"}}"{{end}}>
 						{{svg "octicon-calendar" 16 "gt-mr-3"}}
-						{{DateTime "long" .Issue.DeadlineUnix}}
+						{{DateTime "long" .Issue.DeadlineUnix.FormatDate}}
 					</div>
 					<div>
 						{{if and .HasIssuesOrPullsWritePermission (not .Repository.IsArchived)}}