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Biomedical Ti-25Ta-3Ag alloys were prepared via spark plasma sintering (SPS). The microstructure, morphology and phases of the alloy were characterized by XRD and SEM. The effects of sintering temperature on the electrochemical corrosion properties were investigated in artificial simulated body fluid (Hank"s solution) by open-circuit potential, potentiodynamic polarization and electrochemical impedance spectroscopy. The results show that there are α phase (irregular polygon), martensite α" phase (needle) and β phase (platelets) in the sinter of Ti-25Ta-3Ag, and the elemental Ag (white particle) precipitation at the grain boundary. Electrochemical experiments show that the corrosion resistance of the alloy is improved with the increasing of sintering temperature. The main factors of the excellent corrosion resistance of the alloy in artificial simulated body fluids was owing to Ag addition in the alloy which improves the corrosion potential as well as Ag precipitates at the grain boundary due to the high corrosion resistance of Ag, so that the grain boundary was less prone to corrosion. On the other hand, the passivation film formed on the surface of the alloy which consists of TiO₂ and Ta₂O₅ oxides and low ionic oxides of Ti and Ta as well as metal Ag precipitations, the stability and protection of were enforced.