Because the quadrotor has the features of instability, nonlinear and strong coupling, so attitude control is particularly important in the process of aircraft flight mission. In this paper, the spacecraft attitude control algorithm is studied. First of all, a reasonable coordinate system for quadrotor is established. According to the angle measured by angle sensor, the attitude transformation matrix expressed by quaternion is obtained. According to the principle of aerodynamics and Newton's second law, the flight dynamics model is set up, and the control inputs from four independent channels are obtained, which can control the attitude of quadrotor by controlling the acceleration in all directions.