diff --git a/glance/api/v2/image_data.py b/glance/api/v2/image_data.py
index 928b3ba..8b4938f 100644
--- a/glance/api/v2/image_data.py
+++ b/glance/api/v2/image_data.py
@@ -227,7 +227,10 @@ class ResponseSerializer(wsgi.JSONResponseSerializer):
             response.headers['Content-MD5'] = image.checksum
         # NOTE(markwash): "response.app_iter = ..." also erroneously resets the
         # content-length
-        response.headers['Content-Length'] = str(image.size)
+        # If returning partial content Content-Length should be set to chunk_size
+        response.headers['Content-Length'] = \
+            str(chunk_size) if chunk_size != 0 else str(image.size)
+
 
     def upload(self, response, result):
         response.status_int = 204