diff --git a/src/file-name-completion.scm b/src/file-name-completion.scm
index 1d974a6..d7fdef2 100644
--- a/src/file-name-completion.scm
+++ b/src/file-name-completion.scm
@@ -51,7 +51,10 @@
 (define (dir-executables/prefix dir prefix)
   (if (file-readable? dir)
       (map file-name-nondirectory
-           (let ((files (glob (string-append dir "/" prefix "*"))))
+           (let ((files (glob (string-append (glob-quote dir)
+                                             "/"
+                                             (glob-quote prefix)
+                                             "*"))))
               (if *completion-check-executable*
                   (filter executable? files)
                   files)))