In this paper, the image processing method of flow field interferograms containing shock wave has been investigated. The method includes an algorithm of rapid fringes thinning, an algorithm of extracting shock wave-fronts and an algorithm of registering time-serial shock wave- fronts. An application software based on these algorithms is developed for use with the PC-VISION 100 image processing system. The experimental results show that this method can be used to calculate the propagation velocity and pressure distribution of shock wave-fronts and the functions of flow field interferogram are increased.