Abstract: Using the Sinusoidal expression of Solar elevation angle,the mathematical formula of the length of the object shadow and the solar elevation angle, the local latitude and longitude and the declination angle are deduced. Accordingly,The least squares constrained programming mathematical model is established to determine the location and date of the video recording by using the rule of the object shadow length in the video data and the imaging principle of the camera.Finally, some applications of this method in real life are discussed.