In order to solve small size quadrotor hovering problem under worse satellite signal environment, this paper puts forward a hover scheme based on optical flow method. PX4FLOW optical flow sensor is applied in this scheme. In order to reduce ground texture feature influence on optical flow field calculation, the MSE (Minimum mean Square Error) block matching criterion is used; In order to improve sub pixel localization algorithm extraction accuracy, this paper also adopts gauss curve fitting as extraction algorithm. Based on aircraft moving speed relative to the ground collected by optical flow sensor PX4FLOW, this paper reduces aircraft movement speed relative to the ground by using incremental PID controller, make its converge to zero. Experiments show that the scheme can improve the aircraft hovering stability under the worse satellite signal environment and it has a certain practical value.