Abstract: Objective With the increasing demand for lightweight materials, the reliable connection between carbon fiber reinforced thermoplastics (CFRTP) and aluminum alloys has become a research hotpot. This paper aims to research influence of intermediate layer on microstructure of CFRTP/Al laser welded joint. Methods This article uses laser welding method to add 0.1 mm thick Cu and 0.01 mm, 0.03 mm and 0.05 mm thick Ti intermediate layers respectively, and conducts welding experiments on CFRTP/Al alloy. By establishing a finite element model of laser welding, the temperature field during the welding process is simulated and analyzed, and compared with experimental results. Results Results show that when the thickness of Ti is 0.03 mm, the highest heat is concentrated in the interface area, which is conducive to the reliable connection between the two. Welding interface obtained by adding a 0.03 mm thick Ti intermediate layer is continuous and has a continuous diffusion layer, and the shear strength of the CFRTP/Al laser welded joint reaches a maximum of 76 MPa. Conclusion The finite element model can effectively predict the temperature field distribution of welded joints, and the simulation results are consistent with experimental data. It can provide theoretical guidance for optimizing welding parameters and lay the foundation for achieving high-quality welding between CFRTP/Al alloys.