diff --git a/webrtc/system_wrappers/source/thread_posix.cc b/webrtc/system_wrappers/source/thread_posix.cc
index dd78a70efe..145207b1d9 100644
--- a/webrtc/system_wrappers/source/thread_posix.cc
+++ b/webrtc/system_wrappers/source/thread_posix.cc
@@ -59,10 +59,6 @@
 #include <sys/prctl.h>
 #endif
 
-#if defined(WEBRTC_MAC)
-#include <mach/mach.h>
-#endif
-
 #include "system_wrappers/interface/critical_section_wrapper.h"
 #include "system_wrappers/interface/event_wrapper.h"
 #include "system_wrappers/interface/trace.h"
@@ -148,8 +144,6 @@ ThreadPosix::ThreadPosix(ThreadRunFunction func, ThreadObj obj,
 uint32_t ThreadWrapper::GetThreadId() {
 #if defined(WEBRTC_ANDROID) || defined(WEBRTC_LINUX)
   return static_cast<uint32_t>(syscall(__NR_gettid));
-#elif defined(WEBRTC_MAC)
-  return static_cast<uint32_t>(mach_thread_self());
 #else
   return reinterpret_cast<uint32_t>(pthread_self());
 #endif