To obtain the thermal ablation law of nylon materials under laser irradiation, the infrared imaging was used to explore thermal ablation phenomena of nylon materials under continuous infrared laser irradiation. A camera and an infrared thermal imager were used to record the main phenomena of laser ablation and its temperature field，and a comparison between experiment results and ANSYS simulation was performed. When the nylon was irradiated by using a 976 nm laser beam with an output power density of 1×105 W/m2 and a spot semi-diameter of 10 mm, the experiments show that the temperature of nylon rises quickly at first, then ,expands, melts and decomposes. As time goes on, the temperature of nylon changes slowly, and the melted parts degenerate into the spot edge. When the temperature of nylon reaches certain value, it is no longer rise. Affected by beam quality, material heterogeneous, melted parts degenerated and so on,it indicates that the experimental ablation results and the theoretical results are slightly different, but basically acceptable, which verifies the feasibility of the proposed method and ANSYS simulation.