The welding effect of heterogeneous compatible polymers was poor due to the difference of temperature properties. In order to improve the laser transmission welding strength, laser transmission welding assisted by infrared heating lamp to heate superstructure material with high melting temperature was used. The welding ability was analyzed theoretically and experimentally from four aspects: optical property, temperature property, compatibility and heat absorption test of upper layer material. Response surface methodology was used to optimize process parameters and the optimum combination of process parameters was obtained. A 3-D microscope was used to study the fracture morphology and failure modes of weldments. The effect of air bubbles on the welding ability was also analyzed. The results show that the maximum shear force of the welding with infrared heating lamp can reach about 1.5 times of that without infrared heating lamp. The assistance of infrared heating lamp can effectively solve the problem that the welding effect of heterogeneous polymers is not ideal because ofgreat difference of temperature attributes.