diff --git a/libraries/AP_OpticalFlow/AP_OpticalFlow.cpp b/libraries/AP_OpticalFlow/AP_OpticalFlow.cpp
index 2b86e63f73..2927eb4d32 100644
--- a/libraries/AP_OpticalFlow/AP_OpticalFlow.cpp
+++ b/libraries/AP_OpticalFlow/AP_OpticalFlow.cpp
@@ -26,6 +26,7 @@ const AP_Param::GroupInfo AP_OpticalFlow::var_info[] = {
     // @Param: _TYPE
     // @DisplayName: Optical flow sensor type
     // @Description: Optical flow sensor type
+    // @SortValues: AlphabeticalZeroAtTop
     // @Values: 0:None, 1:PX4Flow, 2:Pixart, 3:Bebop, 4:CXOF, 5:MAVLink, 6:DroneCAN, 7:MSP, 8:UPFLOW
     // @User: Standard
     // @RebootRequired: True