The calculation method of shock wave energy source in discharge chamber of excimer laser was analyzed. Two-dimensional simulation of the physical process of discharge shock wave was carried out by Fluent software. The evolution process of transverse and longitudinal shock waves in 300 μs was revealed. In this process, the distributions of gas velocity, density, pressure, and temperature are obtained. Based on the analysis of the simulation results, the key points in the design of high repetition rate discharge chamber and the processing methods are given. The reference basis for choosing parameters such as the size and boundary of discharge chamber is put forward.