Abstract: In the process acquiring three-dimensional information from the twodimensional picture, the camera calibration is one of essential steps. Moreover, the result of the camera calibration will affect the performance of the machine vision system to a great extent. In the camera calibration process, the camera imaging relations are accurately described using the nonlinear camera model to gain the more accurate camera parameters for improving the performance of the machine vision systems. Finally, the simulation result of the nonlinear camera model calibration is given.