diff --git a/lark/tools/nearley.py b/lark/tools/nearley.py
index 6db2dd9..4adac3a 100644
--- a/lark/tools/nearley.py
+++ b/lark/tools/nearley.py
@@ -2,6 +2,7 @@
 
 import os.path
 import sys
+import codecs
 
 
 from lark import Lark, InlineTransformer, Transformer
@@ -113,7 +114,7 @@ def _nearley_to_lark(g, builtin_path, n2l, js_code, folder_path, includes):
                 path = os.path.join(folder, arg[1:-1])
                 if path not in includes:
                     includes.add(path)
-                    with open(path) as f:
+                    with codecs.open(path, encoding='utf8') as f:
                         text = f.read()
                     rule_defs += _nearley_to_lark(text, builtin_path, n2l, js_code, os.path.abspath(os.path.dirname(path)), includes)
             else:
@@ -168,17 +169,18 @@ def create_code_for_nearley_grammar(g, start, builtin_path, folder_path):
 
     return ''.join(emit_code)
 
-def main():
-    if len(sys.argv) < 3:
-        print("Reads Nearley grammar (with js functions) outputs an equivalent lark parser.")
-        print("Usage: %s <nearley_grammar_path> <start_rule> <nearley_lib_path>" % sys.argv[0])
-        return
-
-    fn, start, nearley_lib = sys.argv[1:]
-    with open(fn) as f:
+def main(fn, start, nearley_lib):
+    with codecs.open(fn, encoding='utf8') as f:
         grammar = f.read()
     print(create_code_for_nearley_grammar(grammar, start, os.path.join(nearley_lib, 'builtin'), os.path.abspath(os.path.dirname(fn))))
 
 
 if __name__ == '__main__':
-    main()
+    if len(sys.argv) < 4:
+        print("Reads Nearley grammar (with js functions) outputs an equivalent lark parser.")
+        print("Usage: %s <nearley_grammar_path> <start_rule> <nearley_lib_path>" % sys.argv[0])
+        sys.exit(1)
+
+    fn, start, nearley_lib = sys.argv[1:]
+
+    main(fn, start, nearley_lib)
diff --git a/tests/test_nearley/grammars/include_unicode.ne b/tests/test_nearley/grammars/include_unicode.ne
new file mode 100644
index 0000000..b04c2a9
--- /dev/null
+++ b/tests/test_nearley/grammars/include_unicode.ne
@@ -0,0 +1,3 @@
+@include "unicode.ne"
+
+main -> x
diff --git a/tests/test_nearley/grammars/unicode.ne b/tests/test_nearley/grammars/unicode.ne
new file mode 100644
index 0000000..c930830
--- /dev/null
+++ b/tests/test_nearley/grammars/unicode.ne
@@ -0,0 +1 @@
+x -> "±a"
diff --git a/tests/test_nearley/test_nearley.py b/tests/test_nearley/test_nearley.py
index 0fbe239..e980f9f 100644
--- a/tests/test_nearley/test_nearley.py
+++ b/tests/test_nearley/test_nearley.py
@@ -1,14 +1,17 @@
+# -*- coding: utf-8 -*-
 from __future__ import absolute_import
 
 import unittest
 import logging
 import os
+import codecs
 
 logging.basicConfig(level=logging.INFO)
 
-from lark.tools.nearley import create_code_for_nearley_grammar
+from lark.tools.nearley import create_code_for_nearley_grammar, main as nearley_tool_main
 
-NEARLEY_PATH = os.path.abspath(os.path.join(os.path.dirname(__file__), 'nearley'))
+TEST_PATH    = os.path.abspath(os.path.dirname(__file__))
+NEARLEY_PATH = os.path.join(TEST_PATH, 'nearley')
 BUILTIN_PATH = os.path.join(NEARLEY_PATH, 'builtin')
 
 class TestNearley(unittest.TestCase):
@@ -59,6 +62,23 @@ class TestNearley(unittest.TestCase):
         parse('b')
         parse('c')
 
+    def test_utf8(self):
+        grammar = u'main -> "±a"'
+        code = create_code_for_nearley_grammar(grammar, 'main', BUILTIN_PATH, './')
+        d = {}
+        exec (code, d)
+        parse = d['parse']
+
+        parse(u'±a')
+
+    def test_utf8_2(self):
+        fn = os.path.join(TEST_PATH, 'grammars/unicode.ne')
+        nearley_tool_main(fn, 'x', NEARLEY_PATH)
+
+    def test_include_utf8(self):
+        fn = os.path.join(TEST_PATH, 'grammars/include_unicode.ne')
+        nearley_tool_main(fn, 'main', NEARLEY_PATH)
+
 
 if __name__ == '__main__':
     unittest.main()