Titanium is well known for its high corrosion resistance. It may be used in the marine industry. In this study, the passivation behavior of titanium was investigated in artificial seawater. It was found that some anions in the artificial seawater could influence the passivation current densities of Ti. The anodic current peak at around 1.6V/SCE on the passivation curve could be associated with dissolution of the passive film. Oxygen evolution could occur at an even more positive potential. The surface films formed at different potentials exibited different biofouling performance.