diff --git a/src/diagrams/class/parser/classDiagram.jison b/src/diagrams/class/parser/classDiagram.jison
index 164562ebcd..b3affe07ae 100644
--- a/src/diagrams/class/parser/classDiagram.jison
+++ b/src/diagrams/class/parser/classDiagram.jison
@@ -14,7 +14,7 @@
 <type_directive>":"                                             { this.popState(); this.begin('arg_directive'); return ':'; }
 <type_directive,arg_directive>\}\%\%                            { this.popState(); this.popState(); return 'close_directive'; }
 <arg_directive>((?:(?!\}\%\%).|\n)*)                            return 'arg_directive';
-\%\%(?!\{)*[^\n]*(\r?\n)+                                       /* skip comments */
+\%\%(?!\{)*[^\n]*(\r?\n?)+                                      /* skip comments */
 \%\%[^\n]*(\r?\n)*                                              /* skip comments */
 (\r?\n)+                return 'NEWLINE';
 \s+                     /* skip whitespace */