The ablation damage caused by laser beam to targets is investigated. The laser disturbance and ablation damage principles are analyzed by the aid of the isochronal irradiation at different power, laser irradiation at different incident angle and solar cell destructive tests. The variation of the solar cell output power with the laser irradiation time is related with the power density of incident beam. The power density inferior to the threshold may leads a decline of solar cell output, which is restorable and temporary. The consequential ablation damage is caused by heat effect of laser. In contrast, the power density in great magnitude may lead a serious ablation damage that is not restorable.