The characteristics wind field impact flight safety, trajectory keeping, and navigation performance of Micro Unmanned Aerial Vehicles (MUAV) directly. Accurate wind field measurement is a premise for MUAVs to take various pre-reactions to gust disturbance. Due to its small size, light weight, and low speed, MUAV is easily affected by gust disturbance during its flight at low altitude. Real time wind speed estimation and flight control strategy adjusting can reduce the impact of gust and enhance flight safety. This paper proposes a method of using airborne IMU, GPS, and pressure sensors to estimate wind speed. Experimental results show that this method can effectively estimate wind speed accurately, and has important application value.