diff --git a/lib/PerlUsersJP/Builder.pm b/lib/PerlUsersJP/Builder.pm
index 15c6fb2e..723376af 100644
--- a/lib/PerlUsersJP/Builder.pm
+++ b/lib/PerlUsersJP/Builder.pm
@@ -355,7 +355,9 @@ sub format_text {
     my ($self, $text, $format) = @_;
 
     if ($format eq 'markdown') {
-        return Text::Markdown::markdown($text);
+        my $html = Text::Markdown::markdown($text);
+        $html =~ s/<code>/<code class="prettyprint">/g;
+        return $html
     }
     elsif ($format eq 'hatena') {
         no warnings qw(once);
@@ -381,6 +383,8 @@ sub format_text {
         $parser->html_header('');
         $parser->html_footer('');
         $parser->parse_string_document("=pod\n\n$text");
+        $out =~ s/<code>/<code class="prettyprint">/g;
+        return $out
     }
     else {
         die "unsupported format: $format";