diff --git a/libraries/AP_OpticalFlow/AP_OpticalFlow.h b/libraries/AP_OpticalFlow/AP_OpticalFlow.h
index 84012bf735..00818964ab 100644
--- a/libraries/AP_OpticalFlow/AP_OpticalFlow.h
+++ b/libraries/AP_OpticalFlow/AP_OpticalFlow.h
@@ -38,7 +38,6 @@
 
 
 class OpticalFlow_backend;
-class AP_AHRS;
 
 class OpticalFlow
 {