In order to improve the bioactivity of tantalum, NaOH solution was applied to tantalum, and the optimal concentration of alkali treatment was explored by simulating somatic fluid (SBF) soaking experiment. Alkali-treated tantalum was pre-calcified in CaCl2 solution and K2HPO4 solution, respectively. Tantalum after 0.7mol/L alkali treatment, soaked in SBF for 2 weeks, the surface can be covered with hydroxyapatite. After pre-calcification, tantalum soaked in SBF for 4 days, the surface can be covered with a layer of hydroxyapatite, indicating that pre-calcification substantially increase the bioactivity of tantalum. The mechanism is pre-calcification can make the sample surface quickly complete the nucleation of calcium and phosphorus compounds, immersed in SBF hydroxyapatite can grow rapidly.