The experiment of 1.06 μm laser disturbing visible CCD image system was carried out, and the phenomenon of crosstalk, crosstalk expanding, full screen saturation and black-and-white spots distributing full screen were observed. With the method of finite element analysis, the temperature rise of detector induced by laser irradiating in the experiment above was simulated. Through numeric analysis, it was found that as temperature rose, dark-current increased while pixel saturation threshold decreased. Especially, when temperature was higher than 350 K, the trend was extremely enhanced. Considering the simulation outcome and changes of dark-current as well as pixel saturation threshold, the experiment phenomenon was properly explained. Results indicated that besides photoelectron produced by photoelectric conversion, the temperature rise induced by laser irradiating and corresponding changes of dark-current as well as pixel saturation threshold was important influencing factor to saturation effect of CCD.