diff --git a/spacy/tests/regression/test_issue600.py b/spacy/tests/regression/test_issue600.py
new file mode 100644
index 000000000..2ab8e9c25
--- /dev/null
+++ b/spacy/tests/regression/test_issue600.py
@@ -0,0 +1,8 @@
+from __future__ import unicode_literals
+from ...tokens import Doc
+from ...vocab import Vocab
+
+
+def test_issue600():
+    doc = Doc(Vocab(tag_map={'NN': {'pos': 'NOUN'}}), words=['hello'])
+    doc[0].tag_ = u'NN'