Abstract: In order to analyze the damage characteristics of mechanical fastened composite laminates subjected to lightning strike, mathematical analysis model of the ablation damage of composite laminate structure with fastener was constructed based on the principle of energy balance. According to the model, an effective three dimensional thermal-electrical coupling analysis finite element model of composite laminate structure with fastener subjected to lightning current has been established based on ABAQUS, and lightning strike ablation damage under different potential boundary conditions was analyzed. Analysis results indicate that:lightning current could pass through the thickness direction of the laminate due to the existence of the metal fastener, then distribute to all layers, and finally conducted in in-plane of layer, conductive ability of different layup orientations was dependent on the potential gradient direction and electrical conductivity along the potential gradient direction; different potential boundary conditions was corresponding to different potential distribution in layers, resulting in conductive ability of different layup orientations was changed, and then caused different lightning strike ablation damage distribution. According to the investigation in this paper, the lightning strike ablation damage characteristic of composite laminate with fastener can be qualitatively recognized.