A new method to measure the three dimensional (3D) shape of the aspheric mirror is proposed. In the measurement, a liquid crystal display(LCD)screen displays the sine fringe pattern and a camera captures the deformed fringe pattern generated by the reflection of the mirror. And the screen and the camera are translated along the measured mirror axis, respectively. At each movement, the camera records the fringe patterns from the screen located at two different positions. By phase shifting technique, the phase information in the deformed fringe pattern can be gotten. Every camera pixel corresponds to a point on the tested mirror and its coordinate and slope can be determined. By integral processing, the 3D shape of the measured mirror can be reconstructed. This method doesn’t need interferometer and assistant mirror. So it can reconstruct the tested mirror flexibly and cheaply. Moreover, this method owns strong ability of anti-noise. With large noise, this method also can reconstruct the 3D shape of aspheric mirror. Computer simulations and preliminary experiment validate the feasibility of this method.