The experiment of 1.06μm laser damage visible imaging system individually at the state of CW(continuous wave),repetitive frequency of 40KHz and 5KHz was carried out. The damage threshold corresponding to each state was measured. It was found that the threshold of repetitive frequency laser was lower than that of CW laser, and the threshold of 5KHz repetitive frequency laser was lower than that of 40KHz laser. With the method of finite element analysis, the temperature change and thermal-stress distribution of detector material induced by CW and repetitive frequency laser irradiation were simulated. By analyzing temperature peak effect and thermal-stress effect of repetitive frequency laser, the reason why repetitive frequency laser had better damage effect was properly explained. By comparing the temperature rise of material induced by laser of different repetitive frequency, the conclusion that laser of lower repetitive frequency had better damage effect was obtained.