Heterointerface induced crystallographic transformation, as a very unique interface phenomenon, has been recently reported in several experiment studies, but its origin has not yet been clarified. In this study, taking the Ni(111)/Fe(110) interface as an exemplary case, we investigate the atomic structures, energetic, and the responsible phase transition mechanism of FCC/BCC heterogeneous interfaces from the first principles. The results predicted the most energy favored structure to be {111}fcc/{110}bcc (K-S). The crystallographic transition occurs only within the near-interface Ni layers. The responsible mechanism is mainly due to interfacial commensuration strains, without involving the change of atom magnetic moments at the interface.