diff --git a/lisp/init-project.el b/lisp/init-project.el
index fbdac59..8be2ad8 100644
--- a/lisp/init-project.el
+++ b/lisp/init-project.el
@@ -29,9 +29,10 @@
 (defun my/add-project (dir)
   "手动将 DIR 添加到 project.el 的项目列表中。"
   (interactive "D添加项目目录: ")
-  (let ((projects (project-known-project-roots)))
-    (unless (member dir projects)
-      (setq projects (append projects (list dir)))
+  (let ((projects (mapcar (lambda (p) (if (listp p) p (list p)))
+                          (project-known-project-roots))))
+    (unless (member (list dir) projects)
+      (setq projects (append projects (list (list dir))))
       (setq project--list projects)
       ;; 保存到 projects 文件，而不是 custom.el
       (with-temp-file project-list-file