diff --git a/pandas/tests/test_index.py b/pandas/tests/test_index.py
index b7a18da3924c8..29b02c195680f 100644
--- a/pandas/tests/test_index.py
+++ b/pandas/tests/test_index.py
@@ -1886,6 +1886,28 @@ def test_reindex_preserves_tz_if_target_is_empty_list_or_array(self):
         self.assertEqual(str(index.reindex([])[0].tz), 'US/Eastern')
         self.assertEqual(str(index.reindex(np.array([]))[0].tz), 'US/Eastern')
 
+    def test_round(self):
+        index = pd.DatetimeIndex([ pd.Timestamp('20120827 12:05:00.002'),
+                                   pd.Timestamp('20130101 12:05:01'),
+                                   pd.Timestamp('20130712 15:10:00'),
+                                   pd.Timestamp('20130712 15:10:00.000004') ])
+
+        result = index.round('1s')
+
+        tm.assert_index_equal(result, pd.DatetimeIndex([
+                                   pd.Timestamp('20120827 12:05:00'),
+                                   pd.Timestamp('20130101 12:05:01'),
+                                   pd.Timestamp('20130712 15:10:00'),
+                                   pd.Timestamp('20130712 15:10:00') ]) )
+
+        result = index.round('1h')
+
+        tm.assert_index_equal(result, pd.DatetimeIndex([
+                                   pd.Timestamp('20120827 12:00:00'),
+                                   pd.Timestamp('20130101 12:00:00'),
+                                   pd.Timestamp('20130712 15:00:00'),
+                                   pd.Timestamp('20130712 15:00:00') ]) )
+
 
 class TestPeriodIndex(Base, tm.TestCase):
     _holder = PeriodIndex
diff --git a/pandas/tseries/index.py b/pandas/tseries/index.py
index 202e30cc2eb5e..128fe13a62c4a 100644
--- a/pandas/tseries/index.py
+++ b/pandas/tseries/index.py
@@ -592,6 +592,11 @@ def _is_dates_only(self):
         from pandas.core.format import _is_dates_only
         return _is_dates_only(self.values)
 
+    def round(self, freq):
+        if isinstance(freq, compat.string_types):
+            freq = to_offset(freq).nanos
+        return DatetimeIndex(((self.asi8/freq).round()*freq).astype(np.int64))
+
     @property
     def _formatter_func(self):
         from pandas.core.format import _get_format_datetime64