diff --git a/autoload/vimwiki/diary.vim b/autoload/vimwiki/diary.vim
index fcd176a..d6cd9e9 100644
--- a/autoload/vimwiki/diary.vim
+++ b/autoload/vimwiki/diary.vim
@@ -65,7 +65,7 @@ fun! s:read_captions(files) "{{{
   let result = {}
   for fl in a:files
     " remove paths and extensions
-    let fl_key = fnamemodify(fl, ':t:r')
+    let fl_key = substitute(fnamemodify(fl, ':t'), VimwikiGet('ext').'$', '', '')
 
     if filereadable(fl)
       for line in readfile(fl, '', s:vimwiki_max_scan_for_caption)