In this work, the current mainstream cold spray particle bonding formation mechanisms were systematically summarized and compared to provide reference for the regulation of cold spray deposition properties and subsequent research. The concepts, principles and characteristics about main bonding mechanisms including the adiabatic shear instability bonding mechanism, the stress wave release-induced material jet formation bonding mechanism and the high-speed collision-induced particle surface oxide film breaking bonding mechanism were summarized. Meanwhile, through the investigation of a large number of literatures, the contradictions and deficiencies of these existing theories were pointed out. The guiding significance of the existing theory of inter-particle bonding formation to the quality control of cold spray deposition was analyzed. At last, based on the shortcomings of current mechanisms, the research on the interface bonding mechanism of cold spray particles was prospected.