A new method for estimating the attitude of spinning missile was proposed.Firstly, according to the nature of spinning missile, a special sun sensor is designed to measure the solar vector instead of the commonly used accelerometer and magnetometer in MEMS sensor to correct the gyro bias.The solar vector measuring device comprises a transparent shell, photocell array, real-time clock and controller.When the sun light illuminates the photocell array through the transparent shell, the photocell array can convert the solar energy into the electric potential signal.According to the size of the solar energy and the angle of the photocell, combined with the accurate time provided by the real-time clock, the solar vector of this moment is obtained through main controller processing.Then, the Kalman filer state equation and observation equation established by using the quaternion differential equation is adopted to estimate the spinning missile attitude.The simulation results show that this method can obtain the higher accuracy attitude angle of spinning missile.