Abstract: For a new developed excimer laser system,the performance of laser gas is very important for the scale of the hybrid gas is closely relative to single pulse energy,stability of discharge,laser lifetime and so on.In order to obtain the optimum premix gas component,the corresponding experiments were accomplished in the own developed compact XeCl excimer laser system.The influence of Xe,HCl gas on the performance was analyzed.For both Ne and He buffer gas,the difference of the excimer laser performance was obtained by the theoretical analysis and experimental result.The optimum gas composition as well as the method to enhance laser efficiency was achieved by the relevant experiments results.The results provide the support and the warrant for developing commercial compact excimer laser.