diff --git a/modules/templates/mailer.go b/modules/templates/mailer.go
index a257e7c1da..355a9d6daf 100644
--- a/modules/templates/mailer.go
+++ b/modules/templates/mailer.go
@@ -13,6 +13,7 @@ import (
 
 	"code.gitea.io/gitea/modules/log"
 	"code.gitea.io/gitea/modules/setting"
+	"code.gitea.io/gitea/modules/util"
 	"code.gitea.io/gitea/modules/watcher"
 )
 
@@ -65,6 +66,7 @@ func Mailer(ctx context.Context) (*texttmpl.Template, *template.Template) {
 			}
 
 			assetName := strings.TrimSuffix(name, ".tmpl")
+			assetName = util.PathJoinRelX(assetName)
 			log.Trace("Adding mailer template for %s from %q", assetName, path)
 			buildSubjectBodyTemplate(subjectTemplates,
 				bodyTemplates,