A new joining process for thin metallic and continuous carbon fiber reinforced thermosetting plastic (CFRP) sheets is proposed. This joining process is a hybrid of chemical bonding and plastic deformation, usable for ultra-lightweight structures. In contrast to conventional joining methods, such as rivet joining with an adhesive, the proposed method does not require any additional components and can eliminate holes that would cut the continuous carbon fibers and cause stress concentration. Hence, a smaller weight and a higher joining quality can be attained, especially for thin sheets. Aiming at making comparison and demonstrating the applicability of the proposed hybrid joining method, two thermosetting CFRP sheets with different laminates were used as lap adherends in the experiment. The effects of the deformation temperature, the use of a dummy sheet and the relative positions of the sample and dummy sheet on the joining quality were systematically investigated and optimized. The optimal hybrid joint shows high-quality bonding without delamination or adhesive failure. The tensile shear test of single-lap A2017P-CFRP hybrid joints manufactured under optimal experimental conditions indicates that, compared with adhesive bonding and conventional rivet joining with an adhesive, the proposed joining method has obvious superiority in terms of tensile shear load, slip displacement and absorption energy.