Abstract: The study of the transition metal isotopic geochemistry is one of the latest developing directions in recent years, which has been used in many fields such as sedimentary geochemistry, cosmochemistry, ore-forming process, magmatism and biology. The implications and the results of the transition metal isotopes in the study of seafloor hydrothermal activity have been introduced. The authors pointed out that the use of transition metal isotopes in hydrothermal activity is very important in future study. Finally, the authors discussed the developing directions in this field, including:(1) maintaining the ample data of the transition metal isotopes, (2) strengthening the study of experimental simulation, (3) further studying the effect of the seafloor hydrothermal activity on the circle and equilibrium of the transition metal isotopes in the ocean.