diff --git a/google/resumable_media/_download.py b/google/resumable_media/_download.py
index 7f489d2e..7b67ad20 100644
--- a/google/resumable_media/_download.py
+++ b/google/resumable_media/_download.py
@@ -41,6 +41,7 @@ class DownloadBase(object):
             the downloaded resource can be written to.
         start (int): The first byte in a range to be downloaded.
         end (int): The last byte in a range to be downloaded.
+        user_agent (Optional[str]) : Custom user agent to be sent
         headers (Optional[Mapping[str, str]]): Extra headers that should
             be sent with the request, e.g. headers for encrypted data.
 
@@ -51,11 +52,12 @@ class DownloadBase(object):
     """
 
     def __init__(self, media_url, stream=None,
-                 start=None, end=None, headers=None):
+                 start=None, end=None, user_agent=None, headers=None):
         self.media_url = media_url
         self._stream = stream
         self.start = start
         self.end = end
+        self.user_agent = user_agent
         if headers is None:
             headers = {}
         self._headers = headers
diff --git a/google/resumable_media/requests/download.py b/google/resumable_media/requests/download.py
index d0bcd990..9f30cb15 100644
--- a/google/resumable_media/requests/download.py
+++ b/google/resumable_media/requests/download.py
@@ -64,6 +64,7 @@ class Download(_helpers.RequestsMixin, _download.Download):
         end (int): The last byte in a range to be downloaded. If not
             provided, but ``start`` is provided, will download from the
             ``start`` to the end of the media.
+        user_agent (Optional[str]) : Custom user agent to be sent
         headers (Optional[Mapping[str, str]]): Extra headers that should
             be sent with the request, e.g. headers for encrypted data.
 
@@ -156,6 +157,8 @@ def consume(self, transport):
                 finished.
         """
         method, url, payload, headers = self._prepare_request()
+        if self.user_agent is not None:
+            headers[u'User-Agent'] = self.user_agent
         # NOTE: We assume "payload is None" but pass it along anyway.
         request_kwargs = {
             u'data': payload,
diff --git a/tests/unit/requests/test_download.py b/tests/unit/requests/test_download.py
index 4e1715cd..3c0faca6 100644
--- a/tests/unit/requests/test_download.py
+++ b/tests/unit/requests/test_download.py
@@ -132,10 +132,11 @@ def test__write_to_stream_with_hash_check_fail(self):
             decode_unicode=False)
 
     def _consume_helper(
-            self, stream=None, end=65536, headers=None, chunks=(),
-            response_headers=None):
+            self, stream=None, end=65536, user_agent=None, headers=None,
+            chunks=(), response_headers=None):
         download = download_mod.Download(
-            EXAMPLE_URL, stream=stream, end=end, headers=headers)
+            EXAMPLE_URL, stream=stream, end=end, user_agent=user_agent,
+            headers=headers)
         transport = mock.Mock(spec=[u'request'])
         transport.request.return_value = _mock_response(
             chunks=chunks, headers=response_headers)
@@ -234,6 +235,14 @@ def test_consume_with_headers(self):
         # Make sure the headers have been modified.
         assert headers == {u'range': range_bytes}
 
+    def test_consume_with_user_agent(self):
+        headers = {}
+        end = 16383
+        user_agent = "Custom-User-Agent-1.0"
+        range_bytes = u'bytes={:d}-{:d}'.format(0, end)
+        self._consume_helper(end=end, user_agent=user_agent, headers=headers)
+        assert headers == {u'range': range_bytes, u'User-Agent': user_agent}
+
 
 class TestChunkedDownload(object):
 
diff --git a/tests/unit/test__download.py b/tests/unit/test__download.py
index ee4e9fc7..a693e353 100644
--- a/tests/unit/test__download.py
+++ b/tests/unit/test__download.py
@@ -35,6 +35,7 @@ def test_constructor_defaults(self):
         assert download._stream is None
         assert download.start is None
         assert download.end is None
+        assert download.user_agent is None
         assert download._headers == {}
         assert not download._finished
         _check_retry_strategy(download)
@@ -42,14 +43,16 @@ def test_constructor_defaults(self):
     def test_constructor_explicit(self):
         start = 11
         end = 10001
+        user_agent = 'custome-user-agent-1.0'
         headers = {u'foof': u'barf'}
         download = _download.DownloadBase(
             EXAMPLE_URL, stream=mock.sentinel.stream,
-            start=start, end=end, headers=headers)
+            start=start, end=end, user_agent=user_agent, headers=headers)
         assert download.media_url == EXAMPLE_URL
         assert download._stream is mock.sentinel.stream
         assert download.start == start
         assert download.end == end
+        assert download.user_agent == user_agent
         assert download._headers is headers
         assert not download._finished
         _check_retry_strategy(download)