diff --git a/bin/pseudohiki2html.rb b/bin/pseudohiki2html.rb
index <HASH>..<HASH> 100644
--- a/bin/pseudohiki2html.rb
+++ b/bin/pseudohiki2html.rb
@@ -74,7 +74,7 @@ class << OPTIONS
   end
 end
 
-FILE_HEADER_PAT = /^\/\//
+FILE_HEADER_PAT = /^(\xef\xbb\xbf)?\/\//
 WRITTEN_OPTION_PAT = {}
 OPTIONS.keys.each {|opt| WRITTEN_OPTION_PAT[opt] = /^(\xef\xbb\xbf)?\/\/#{opt}:\s*(.*)$/ }
ignores BOM at the head of input files