diff --git a/python/ray/dataframe/dataframe.py b/python/ray/dataframe/dataframe.py
index 10b8df9ec..df3be2a54 100644
--- a/python/ray/dataframe/dataframe.py
+++ b/python/ray/dataframe/dataframe.py
@@ -1444,9 +1444,31 @@ class DataFrame(object):
         return result
 
     def diff(self, periods=1, axis=0):
-        raise NotImplementedError(
-            "To contribute to Pandas on Ray, please visit "
-            "github.com/ray-project/ray.")
+        """Finds the difference between elements on the axis requested
+
+        Args:
+            periods: Periods to shift for forming difference
+            axis: Take difference over rows or columns
+
+        Returns:
+            DataFrame with the diff applied
+        """
+        axis = pd.DataFrame()._get_axis_number(axis)
+        partitions = (self._col_partitions if
+                      axis == 0 else self._row_partitions)
+
+        result = _map_partitions(lambda df:
+                                 df.diff(axis=axis, periods=periods),
+                                 partitions)
+
+        if (axis == 1):
+            return DataFrame(row_partitions=result,
+                             columns=self.columns,
+                             index=self.index)
+        if (axis == 0):
+            return DataFrame(col_partitions=result,
+                             columns=self.columns,
+                             index=self.index)
 
     def div(self, other, axis='columns', level=None, fill_value=None):
         """Divides this DataFrame against another DataFrame/Series/scalar.
@@ -1661,7 +1683,7 @@ class DataFrame(object):
             # TODO: group series here into full df partitions to reduce
             # the number of remote calls to helper
             other_series = other_df.iloc[idx['index_within_partition']]
-            curr_index = self._row_metadata._coord_df.iloc[i]
+            curr_index = self._row_metadata._coord_df.loc[i]
             curr_df = self._row_partitions[int(curr_index['partition'])]
             results.append(_deploy_func.remote(helper,
                                                curr_df,
diff --git a/python/ray/dataframe/test/test_dataframe.py b/python/ray/dataframe/test/test_dataframe.py
index 817d849b0..73581fcd5 100644
--- a/python/ray/dataframe/test/test_dataframe.py
+++ b/python/ray/dataframe/test/test_dataframe.py
@@ -226,6 +226,7 @@ def test_int_dataframe():
     test_quantile(ray_df, pandas_df, .5)
     test_quantile(ray_df, pandas_df, .75)
     test_describe(ray_df, pandas_df)
+    test_diff(ray_df, pandas_df)
 
     test_all(ray_df, pandas_df)
     test_any(ray_df, pandas_df)
@@ -390,6 +391,7 @@ def test_float_dataframe():
     test_quantile(ray_df, pandas_df, .5)
     test_quantile(ray_df, pandas_df, .75)
     test_describe(ray_df, pandas_df)
+    test_diff(ray_df, pandas_df)
 
     test_all(ray_df, pandas_df)
     test_any(ray_df, pandas_df)
@@ -715,6 +717,7 @@ def test_nan_dataframe():
     test_quantile(ray_df, pandas_df, .5)
     test_quantile(ray_df, pandas_df, .75)
     test_describe(ray_df, pandas_df)
+    test_diff(ray_df, pandas_df)
 
     test_all(ray_df, pandas_df)
     test_any(ray_df, pandas_df)
@@ -1170,11 +1173,12 @@ def test_describe(ray_df, pandas_df):
     assert(ray_df.describe().equals(pandas_df.describe()))
 
 
-def test_diff():
-    ray_df = create_test_dataframe()
-
-    with pytest.raises(NotImplementedError):
-        ray_df.diff()
+@pytest.fixture
+def test_diff(ray_df, pandas_df):
+    assert(ray_df_equals_pandas(ray_df.diff(), pandas_df.diff()))
+    assert(ray_df_equals_pandas(ray_df.diff(axis=1), pandas_df.diff(axis=1)))
+    assert(ray_df_equals_pandas(ray_df.diff(periods=1),
+                                pandas_df.diff(periods=1)))
 
 
 def test_div():