diff --git a/Kernel/API/Syscall.h b/Kernel/API/Syscall.h
index af5b4eb957..5dcf3b9322 100644
--- a/Kernel/API/Syscall.h
+++ b/Kernel/API/Syscall.h
@@ -6,6 +6,7 @@
 
 #pragma once
 
+#include <AK/Error.h>
 #include <AK/Types.h>
 #include <AK/Userspace.h>
 #include <Kernel/API/POSIX/sched.h>