Abstract: In order to improve the mechanical properties of aluminum-based structures, the flexural strength of CFRP-aluminum alloy composite structures is explored by combining experiments and finite element simulations. The CFRP-aluminum alloy composite structure specimens with different carbon fiber cloth layers （1~4 layers） were prepared, and the flexural strength was tested by the three-point bending （ENF） test. The results show that the reinforcement of carbon fiber cloth significantly improves the bearing capacity of the composite structure, and the flexural strength of the composite structure is significantly improved compared with that of pure aluminum alloy specimens. The failure mode of CFRP-aluminum base is mainly the peeling of the interface of the adhesive layer, and the bearing capacity drops sharply during failure, which reflects that the strength of the interface adhesive layer is the key factor affecting the overall performance of the composite structure. The ENF model based on ABAQUS verifies the reliability of the test data, so as to provide theoretical basis and technical support for the application of CFRP-aluminum alloy composite structure in the field of lightweight.