diff --git a/lisp/org.el b/lisp/org.el
index cde7c03f9..ee471189f 100644
--- a/lisp/org.el
+++ b/lisp/org.el
@@ -5424,6 +5424,7 @@ between words."
 	"\\<\\("
 	(mapconcat
 	 (lambda (x)
+	   (setq x (regexp-quote x))
 	   (while (string-match " +" x)
 	     (setq x (replace-match "\\s-+" t t x)))
 	   x)