diff --git a/Network/Wai/Application/Classic/Field.hs b/Network/Wai/Application/Classic/Field.hs
--- a/Network/Wai/Application/Classic/Field.hs
+++ b/Network/Wai/Application/Classic/Field.hs
@@ -10,6 +10,7 @@
 import qualified Data.Map as Map (toList)
 import Data.Maybe
 import Data.StaticHash (StaticHash)
+import Data.List (delete)
 import qualified Data.StaticHash as SH
 import qualified Data.Text as T
 import Network.HTTP.Date
@@ -68,6 +69,9 @@
       , softwareName cspec
       , ")"
       ]
+
+deleteTransferEncoding :: ResponseHeaders -> ResponseHeaders
+deleteTransferEncoding hdr = delete ("Transfer-Encoding", "chunked") hdr
 
 addForwardedFor :: Request -> ResponseHeaders -> ResponseHeaders
 addForwardedFor req hdr = (hXForwardedFor, addr) : hdr
diff --git a/Network/Wai/Application/Classic/RevProxy.hs b/Network/Wai/Application/Classic/RevProxy.hs
--- a/Network/Wai/Application/Classic/RevProxy.hs
+++ b/Network/Wai/Application/Classic/RevProxy.hs
@@ -81,7 +81,7 @@
     ResponseSource status hdr <$> toSource (lookup hContentType hdr) rdownbody
   where
     mgr = revProxyManager spec
-    fixHeader = addVia cspec req . filter p
+    fixHeader = deleteTransferEncoding . addVia cspec req . filter p
     p (k,_)
       | k == hContentEncoding = False
       | k == hContentLength   = False
diff --git a/wai-app-file-cgi.cabal b/wai-app-file-cgi.cabal
--- a/wai-app-file-cgi.cabal
+++ b/wai-app-file-cgi.cabal
@@ -1,5 +1,5 @@
 Name:                   wai-app-file-cgi
-Version:                0.8.6
+Version:                0.8.7
 Author:                 Kazu Yamamoto <kazu@iij.ad.jp>
 Maintainer:             Kazu Yamamoto <kazu@iij.ad.jp>
 License:                BSD3