Abstract: Based on the rate-equation model of end-pumped alkali vapor laser, the performance of diode-pumped Cs vapor laser was researched. By adjusting the parameters of pump source and vapor cell, the effects of each parameter on the absorption and output performances were analyzed. Results show that the power absorbed by Cs vapor and output laser power become saturated when pump power and ethane pressure increases. The powers also have a Gaussian dependence on the deviation between pump light wavelength and transition wavelength. Besides, the powers increase initially and then begin to decrease when adding more helium into the vapor cell. Furthermore, there exist a critical line-width of pump light and a temperature range to maintain the operation of laser. The simulated results are in line with reported experiments well, which will supply significant reference for further experimental research.