In the high speed flow field, shock wave will cause obvious aero-optics effect, which can induce the excursion and focusing of the ray and so on. In this paper, the relationships of angle excursion and shock intensity are reviewed theoretically in the condition of different incidence angles. In application to actual problem, the shock field is usually simulated by computational fluid dynamics. In order to trace the ray through the simulated shock field, an idea and the matched method are carried out, which can improve the tracing precision. In this way, the tracing step distance is aimed to be self-adaptive to local refraction index gradient and grid geometry scale. At last, the ray tracing method is validated. The result shows that the method has high precision for ray tracing in the shock field.