Abstract: The experimental study on Nd∶YAG laser passively Qswitched by Cr∶YAG is carried out. The focus is given to the influence of pumping power, cavity length, the output coupler transmission and initial transmission on the repetition rate, pulse width and output power of laser output. The experiment results were analyzed and discussed. It can be observed from the curve that an increase of pumping power results in an increase of repetition rate and decrease of pulse width，but the impact of cavity length is on the contrary side. There is an optimized output coupler transmission which can maximize the output power. Different initial transmittances have certain effects on the output. The analyses show that the passive Qswitching technology is applicable to DPL.