Aiming at the damage effects of solar cells under the irradiation of continous wave laser, the output parameter decrease of damaged solar cells and impact induced by laser irradiation are analyzed, the damage mechanisms of solar cells are researched through the observation of morphology of damaged area combined with the equivalent circuit diagram and I-V curves. The results show that laser ablated solar cell resulted in the ablation area is disabled, causes the increase of series resistance and the decrease of parallel resistance at the same time, and finally induces the output performance of solar cell to decrease largely.