diff --git a/ChangeLog.md b/ChangeLog.md
--- a/ChangeLog.md
+++ b/ChangeLog.md
@@ -1,3 +1,7 @@
+## 0.1.7
+
+- Using System.Timeout.timeout.
+
 ## 0.1.6
 
 - Fixing the race condition of `timeout`.
diff --git a/Network/QUIC/Connection/Timeout.hs b/Network/QUIC/Connection/Timeout.hs
--- a/Network/QUIC/Connection/Timeout.hs
+++ b/Network/QUIC/Connection/Timeout.hs
@@ -1,6 +1,3 @@
-{-# LANGUAGE CPP #-}
-{-# LANGUAGE DeriveDataTypeable #-}
-
 module Network.QUIC.Connection.Timeout (
     timeout
   , fire
@@ -8,35 +5,18 @@
   , delay
   ) where
 
-import Data.Typeable
 import Network.QUIC.Event
 import UnliftIO.Concurrent
 import qualified UnliftIO.Exception as E
+import qualified System.Timeout as ST
 
 import Network.QUIC.Connection.Types
 import Network.QUIC.Connector
 import Network.QUIC.Imports
 import Network.QUIC.Types
 
-data TimeoutException = TimeoutException String deriving (Show, Typeable)
-
-instance E.Exception TimeoutException where
-  fromException = E.asyncExceptionFromException
-  toException = E.asyncExceptionToException
-
 timeout :: Microseconds -> String -> IO a -> IO (Maybe a)
-timeout (Microseconds ms) dmsg action = do
-    tid <- myThreadId
-    timmgr <- getSystemTimerManager
-#if defined(mingw32_HOST_OS)
-    let killMe = void $ forkIO $ E.throwTo tid $ TimeoutException dmsg
-#else
-    let killMe = E.throwTo tid $ TimeoutException dmsg
-#endif
-        setup = registerTimeout timmgr ms killMe
-        cleanup key = unregisterTimeout timmgr key
-    E.handleSyncOrAsync (\(TimeoutException _) -> return Nothing) $
-        E.bracket setup cleanup $ \_ -> Just <$> action
+timeout (Microseconds ms) _ action = ST.timeout ms action
 
 fire :: Connection -> Microseconds -> TimeoutCallback -> IO ()
 fire conn (Microseconds microseconds) action = do
diff --git a/quic.cabal b/quic.cabal
--- a/quic.cabal
+++ b/quic.cabal
@@ -1,6 +1,6 @@
 cabal-version:      >=1.10
 name:               quic
-version:            0.1.6
+version:            0.1.7
 license:            BSD3
 license-file:       LICENSE
 maintainer:         kazu@iij.ad.jp