In view of the problem that the coefficient of laser gyro strapdown inertial measurement unit (LSIMU) will change with the time, a novel field calibration method of laser gyro is presented based on the twoaxis position turntable. The method gathers the output signals of LSIMU at three different positions, then nine equation formula are established based on the calibration model. The effect of the rotationalangular velocity of the earth on the nonrotation axis is eliminated through the positive and negative rotations, and the effect of constant drift on the each output axis is also eliminated. The scale factor and the installation error of laser gyro are finally solved. The experiment results show that the proposed threeposition calibration method can calibrate laser gyroscope without high precision turntable and is almost on the same accurate level precision with the traditional method, and can obviously reduce the calibration time.