diff --git a/CHANGES.rst b/CHANGES.rst
index 285de01..bc094fc 100644
--- a/CHANGES.rst
+++ b/CHANGES.rst
@@ -4,6 +4,12 @@ Changelog
 Here you can see the full list of changes between each SQLAlchemy-Utils release.
 
 
+0.30.8 (2015-06-xx)
+^^^^^^^^^^^^^^^^^^^
+
+- Make has_index work with tables without primary keys (#148)
+
+
 0.30.7 (2015-05-28)
 ^^^^^^^^^^^^^^^^^^^
 
diff --git a/sqlalchemy_utils/functions/database.py b/sqlalchemy_utils/functions/database.py
index 3e7b034..040f240 100644
--- a/sqlalchemy_utils/functions/database.py
+++ b/sqlalchemy_utils/functions/database.py
@@ -247,8 +247,9 @@ def has_index(column):
             'Only columns belonging to Table objects are supported. Given '
             'column belongs to %r.' % table
         )
+    primary_keys = table.primary_key.columns.values()
     return (
-        column is table.primary_key.columns.values()[0]
+        (primary_keys and column is primary_keys[0])
         or
         any(
             index.columns.values()[0] is column
diff --git a/tests/functions/test_has_index.py b/tests/functions/test_has_index.py
index 3dfabf1..9c0e1c6 100644
--- a/tests/functions/test_has_index.py
+++ b/tests/functions/test_has_index.py
@@ -39,3 +39,14 @@ class TestHasIndex(object):
     def test_compound_column_index(self):
         assert has_index(self.table.c.is_deleted)
         assert not has_index(self.table.c.is_archived)
+
+    def test_table_without_primary_key(self):
+        Base = declarative_base()
+
+        article = sa.Table(
+            'article',
+            sa.MetaData(),
+            sa.Column('name', sa.String)
+        )
+
+        assert not has_index(article.c.name)