Abstract: To obtain the optimum parameters of the radio frequency (RF) hollow cathode plasma parameters and develop the uniform of the discharge gas distribution, and then improve the uniform of modified material surface, the mathematical model of discharge gas flow of RF hollow cathode plasma was constructed. Applying the Fluent software to simulate the discharge gas distribution, and obtained the optimum discharge gas parameters. The surface modification experiment of battery separator was tested using the selected parameters, the optimum discharge parameters were obtained by testing the maximum alkali absorption quantity of battery separator. The results show that the discharge parameters obtained by experiment were well with the simulated ones, this could prove that the finite element model simulation was feasible and efficient. The optimum discharge parameters was anode aperture of 8 mm, intake air flow rate of 5 L·min-1 and sample position of 20 mm.