diff --git a/django/http/utils.py b/django/http/utils.py
index fcb3fecb6ca..e13dc4cbb64 100644
--- a/django/http/utils.py
+++ b/django/http/utils.py
@@ -31,13 +31,13 @@ def conditional_content_removal(request, response):
         if response.streaming:
             response.streaming_content = []
         else:
-            response.content = ''
+            response.content = b''
         response['Content-Length'] = '0'
     if request.method == 'HEAD':
         if response.streaming:
             response.streaming_content = []
         else:
-            response.content = ''
+            response.content = b''
     return response
 
 
diff --git a/tests/http_utils/tests.py b/tests/http_utils/tests.py
index 7dfd24d721b..06a310a787f 100644
--- a/tests/http_utils/tests.py
+++ b/tests/http_utils/tests.py
@@ -1,10 +1,21 @@
 from __future__ import unicode_literals
 
+import io
+import gzip
+
 from django.http import HttpRequest, HttpResponse, StreamingHttpResponse
 from django.http.utils import conditional_content_removal
 from django.test import TestCase
 
 
+# based on Python 3.3's gzip.compress
+def gzip_compress(data):
+    buf = io.BytesIO()
+    with gzip.GzipFile(fileobj=buf, mode='wb', compresslevel=0) as f:
+        f.write(data)
+    return buf.getvalue()
+
+
 class HttpUtilTests(TestCase):
 
     def test_conditional_content_removal(self):
@@ -33,6 +44,19 @@ class HttpUtilTests(TestCase):
             conditional_content_removal(req, res)
             self.assertEqual(b''.join(res), b'')
 
+        # Issue #20472  
+        abc = gzip_compress(b'abc')
+        res = HttpResponse(abc, status=304)
+        res['Content-Encoding'] = 'gzip'
+        conditional_content_removal(req, res)
+        self.assertEqual(res.content, b'')
+
+        res = StreamingHttpResponse([abc], status=304)
+        res['Content-Encoding'] = 'gzip'
+        conditional_content_removal(req, res)
+        self.assertEqual(b''.join(res), b'')
+
+
         # Strip content for HEAD requests.
         req.method = 'HEAD'