diff --git a/httpretty/core.py b/httpretty/core.py
index 69686458..b5fee9e0 100644
--- a/httpretty/core.py
+++ b/httpretty/core.py
@@ -1130,7 +1130,7 @@ def fill_filekind(self, fk):
             )
 
         for item in string_list:
-            fk.write(utf8(item) + b'\n')
+            fk.write(utf8(item) + b'\r\n')
 
         fk.write(b'\r\n')