diff --git a/Rover/GCS_Mavlink.cpp b/Rover/GCS_Mavlink.cpp
index f47cecfb283a25..e13e35bebc255c 100644
--- a/Rover/GCS_Mavlink.cpp
+++ b/Rover/GCS_Mavlink.cpp
@@ -556,7 +556,9 @@ static const ap_message STREAM_RC_CHANNELS_msgs[] = {
 };
 static const ap_message STREAM_EXTRA1_msgs[] = {
     MSG_ATTITUDE,
+#if AP_SIM_ENABLED
     MSG_SIMSTATE,
+#endif
     MSG_AHRS2,
     MSG_PID_TUNING,
 };