diff --git a/scrapy/responsetypes.py b/scrapy/responsetypes.py
index ad89d9d22..7c5eeac21 100644
--- a/scrapy/responsetypes.py
+++ b/scrapy/responsetypes.py
@@ -71,7 +71,7 @@ class ResponseTypes:
         cls = Response
         if b'Content-Type' in headers:
             cls = self.from_content_type(
-                content_type=headers[b'Content-type'],
+                content_type=headers[b'Content-Type'],
                 content_encoding=headers.get(b'Content-Encoding')
             )
         if cls is Response and b'Content-Disposition' in headers: