diff --git a/reactos/dll/ntdll/def/ntdll_i386.def b/reactos/dll/ntdll/def/ntdll_i386.def
index 8ce9a39b45e..14e92fd96a6 100644
--- a/reactos/dll/ntdll/def/ntdll_i386.def
+++ b/reactos/dll/ntdll/def/ntdll_i386.def
@@ -869,7 +869,7 @@ RtlSetEnvironmentVariable@12
 RtlSetGroupSecurityDescriptor@12
 RtlSetHeapInformation@16
 RtlSetInformationAcl@16
-;RtlSetIoCompletionCallback
+RtlSetIoCompletionCallback@12
 RtlSetLastWin32Error@4
 RtlSetLastWin32ErrorAndNtStatusFromNtStatus@4
 ;RtlSetMemoryStreamSize
diff --git a/reactos/include/ndk/rtlfuncs.h b/reactos/include/ndk/rtlfuncs.h
index 538be4aeb38..5f431a0f306 100644
--- a/reactos/include/ndk/rtlfuncs.h
+++ b/reactos/include/ndk/rtlfuncs.h
@@ -2060,6 +2060,15 @@ RtlQueueWorkItem(
     IN ULONG Flags
 );
 
+NTSYSAPI
+NTSTATUS
+NTAPI
+RtlSetIoCompletionCallback(
+    IN HANDLE FileHandle,
+    IN PRTL_OVERLAPPED_COMPLETION_ROUTINE Function,
+    IN ULONG Flags
+);
+
 NTSYSAPI
 NTSTATUS
 NTAPI
diff --git a/reactos/include/ndk/rtltypes.h b/reactos/include/ndk/rtltypes.h
index 4fcf5bf9eeb..a57ab22a816 100644
--- a/reactos/include/ndk/rtltypes.h
+++ b/reactos/include/ndk/rtltypes.h
@@ -405,6 +405,16 @@ typedef EXCEPTION_DISPOSITION
     IN OUT PVOID DispatcherContext
 );
 
+//
+// Callback for RtlSetIoCompletionCallback
+//
+typedef VOID
+(NTAPI *PRTL_OVERLAPPED_COMPLETION_ROUTINE)(
+    ULONG,
+    ULONG,
+    PVOID
+);
+
 //
 // RTL Library Allocation/Free Routines
 //
diff --git a/reactos/lib/rtl/workitem.c b/reactos/lib/rtl/workitem.c
index 1d262933219..8c95aadce7c 100644
--- a/reactos/lib/rtl/workitem.c
+++ b/reactos/lib/rtl/workitem.c
@@ -879,3 +879,16 @@ Cleanup:
 
     return Status;
 }
+
+/*
+ * @unimplemented
+ */
+NTSTATUS
+NTAPI
+RtlSetIoCompletionCallback(IN HANDLE hFileHandle,
+                           IN PRTL_OVERLAPPED_COMPLETION_ROUTINE Function,
+                           IN ULONG Flags)
+{
+    UNIMPLEMENTED;
+    return STATUS_NOT_IMPLEMENTED;
+}