diff --git a/doc/source/whatsnew/v0.16.0.txt b/doc/source/whatsnew/v0.16.0.txt
index 21b1ddea0e9da..2dbb1f284560d 100644
--- a/doc/source/whatsnew/v0.16.0.txt
+++ b/doc/source/whatsnew/v0.16.0.txt
@@ -96,6 +96,8 @@ Bug Fixes
 - Bug in ``pivot`` and `unstack`` where ``nan`` values would break index alignment (:issue:`7466`)
 
 
+- Fixed bug where minutes and seconds components were zeroed when writing
+  Timestamp objects to Excel using xlwt and xlsxwriter (:issue:`9138`).
 
 
 
diff --git a/pandas/io/excel.py b/pandas/io/excel.py
index 2ece91b5dea11..792b9d554be68 100644
--- a/pandas/io/excel.py
+++ b/pandas/io/excel.py
@@ -16,6 +16,7 @@
 from pandas.compat import map, zip, reduce, range, lrange, u, add_metaclass
 from pandas.core import config
 from pandas.core.common import pprint_thing
+from pandas import Timestamp
 import pandas.compat as compat
 import pandas.compat.openpyxl_compat as openpyxl_compat
 import pandas.core.common as com
@@ -1118,6 +1119,10 @@ def write_cells(self, cells, sheet_name=None, startrow=0, startcol=0):
             val = _conv_value(cell.val)
 
             num_format_str = None
+
+            if isinstance(val, Timestamp):
+                val = val.to_pydatetime()
+
             if isinstance(cell.val, datetime.datetime):
                 num_format_str = self.datetime_format
             elif isinstance(cell.val, datetime.date):
@@ -1239,6 +1244,10 @@ def write_cells(self, cells, sheet_name=None, startrow=0, startcol=0):
 
         for cell in cells:
             num_format_str = None
+
+            if isinstance(cell.val, Timestamp):
+                cell.val = cell.val.to_pydatetime()
+
             if isinstance(cell.val, datetime.datetime):
                 num_format_str = self.datetime_format
             elif isinstance(cell.val, datetime.date):
diff --git a/pandas/io/tests/test_excel.py b/pandas/io/tests/test_excel.py
index 4f97cef3d46d3..95b4c0ace642f 100644
--- a/pandas/io/tests/test_excel.py
+++ b/pandas/io/tests/test_excel.py
@@ -1151,6 +1151,28 @@ def test_swapped_columns(self):
             tm.assert_series_equal(write_frame['A'], read_frame['A'])
             tm.assert_series_equal(write_frame['B'], read_frame['B'])
 
+    def test_datetimes(self):
+        # Test writing and reading datetimes. For issue #9139.
+        _skip_if_no_xlrd()
+
+        datetimes = [datetime(2013, 1, 13, 1, 2, 3),
+                     datetime(2013, 1, 13, 2, 45, 56),
+                     datetime(2013, 1, 13, 4, 29, 49),
+                     datetime(2013, 1, 13, 6, 13, 42),
+                     datetime(2013, 1, 13, 7, 57, 35),
+                     datetime(2013, 1, 13, 9, 41, 28),
+                     datetime(2013, 1, 13, 11, 25, 21),
+                     datetime(2013, 1, 13, 13, 9, 14),
+                     datetime(2013, 1, 13, 14, 53, 7),
+                     datetime(2013, 1, 13, 16, 37, 0),
+                     datetime(2013, 1, 13, 18, 20, 52)]
+
+        with ensure_clean(self.ext) as path:
+            write_frame = DataFrame.from_items([('A', datetimes)])
+            write_frame.to_excel(path, 'Sheet1')
+            read_frame = read_excel(path, 'Sheet1', header=0)
+
+            tm.assert_series_equal(write_frame['A'], read_frame['A'])
 
 def raise_wrapper(major_ver):
     def versioned_raise_wrapper(orig_method):