Abstract: The formation of brittle intermetallic compounds at the interfaces of diffusion bonds in dissimilar materials is the main cause which leads to produce poor bond properties. Therefore it is very important for the diffusion bonding theory development and application to research and controls the formation of intermetallic compounds at the interfaces. The formation of brittle intermetallic compounds at the interfaces of diffusion bonds is the diffusion-controlled reaction process. Furthermore, the phase transformation of phase transformation-diffusion bonding brings more sophisticated interface reaction. In this paper according to the characteristics of phase transformation diffusion bonding, the element diffusion of interface and the growing model of interface intermetallic compounds were established. The computed results were in agreement with the experimental data. It can provide reference to the choice of phase transformation diffusion bonding parameters.