Injection molding of corrosive super engineering plastics and engineering plastics with various fillers is conducted under severe conditions and causes corrosion and wear problems. We have developed boride base cermets, which have excellent corrosion-and wear-resistances, and tried to apply them into plastic molding machine parts. In this paper, the effects of V substitution for Cr on the mechanical properties, corrosion resistance and microstructure of Ni-5.0B-51.0Mo-(17.5-X)Cr-XV (mass%) model cermets were investigated. Both transverse rupture strength (TRS) and hardness increased monotonically with increasing V content and reached 2.94GPa and at 10.0%V, respectively. The improvements of TRS and hardness were attributed to microstructural refinement.