diff --git a/lib/isc/win32/include/isc/platform.h.in b/lib/isc/win32/include/isc/platform.h.in
index 0aeebff249..f27c867de2 100644
--- a/lib/isc/win32/include/isc/platform.h.in
+++ b/lib/isc/win32/include/isc/platform.h.in
@@ -18,13 +18,6 @@
 
 #define ISC_PLATFORM_USETHREADS 1
 
-/*
- * Thread-Local Storage
- */
-#ifndef thread_local
-#define thread_local
-#endif
-
 /*
  * Some compatibility cludges
  */