diff --git a/lib/lrama/command.rb b/lib/lrama/command.rb
index 213b7acb..eff31e46 100644
--- a/lib/lrama/command.rb
+++ b/lib/lrama/command.rb
@@ -8,7 +8,7 @@ def run(argv)
       warning = Lrama::Warning.new
       text = options.y.read
       options.y.close if options.y != STDIN
-      grammar = Lrama::NewParser.new(text).parse
+      grammar = Lrama::NewParser.new(text, options.header_file).parse
       states = Lrama::States.new(grammar, warning, trace_state: (options.trace_opts[:automaton] || options.trace_opts[:closure]))
       states.compute
       context = Lrama::Context.new(states)
diff --git a/lib/lrama/new_parser.rb b/lib/lrama/new_parser.rb
index a18e127a..af28ed21 100644
--- a/lib/lrama/new_parser.rb
+++ b/lib/lrama/new_parser.rb
@@ -10,8 +10,9 @@ class NewParser < Racc::Parser
 
 module_eval(<<'...end parser.y/module_eval...', 'parser.y', 121)
 
-def initialize(text)
+def initialize(text, header_file)
   @text = text
+  @header_path = header_file ? header_file.sub("./", "") : nil
   @lineno = []
   @column = []
 end
@@ -474,7 +475,11 @@ def _reduce_5(val, _values, result)
 
 module_eval(<<'.,.,', 'parser.y', 7)
   def _reduce_6(val, _values, result)
-     @grammar.prologue = val[2]
+    if @header_path
+      @grammar.prologue = "\n#include \"#{@header_path}\"\n" + val[2]
+    else
+      @grammar.prologue = val[2]
+    end
     result
   end
 .,.,