In this paper,a theoretical random walk model for the metal vapor condenser ofmetal vapor lasers is presented.The proposed model was verified qualitatiively byexperiment.Based on this model,a new type of condenser was proposed. Its principle is asfollows:several metal pieces of high metal vapor condensation coefficients were used toadsorb the random walking metal vapor particles that collide upon them, as a result,aprotection of the laser windows from the metal vapor pollution was achieved. A Monte Carlo simulation showed that the ability of antipollution for this new type condenser was much higher than that of the common condenser.