diff --git a/src/ray/rpc/grpc_server.cc b/src/ray/rpc/grpc_server.cc
index 141ee426c..4cbdafb58 100644
--- a/src/ray/rpc/grpc_server.cc
+++ b/src/ray/rpc/grpc_server.cc
@@ -15,6 +15,7 @@
 #include "ray/rpc/grpc_server.h"
 
 #include <grpcpp/impl/service_type.h>
+#include <unistd.h>
 
 #include <boost/asio/detail/socket_holder.hpp>