The work aims to study the electrochemical and corrosion behavior of TC2 titanium alloy in simulated seawater and the effect of deformation. U-shaped sample was prepared and simulated seawater immersion test was conducted. Potential test, polarization curve test, electrochemical impedance spectroscopy, SEM and XRD were employed for analysis. During 240 d im-mersion test in simulated seawater, the impedance value of non-shaped sample surface passive film rapidly increased initially and then slowly increased as time prolonged, and the corrosion potential continued to increase, so the surface electrochemical reaction decreased and the corrosion rate was low. The impedance value of 45° deformation sample surface passive film initially increased slightly and then decreased and finally dropped below the initial impedance values. The impedance value of 90° deformation sample surface passive film steady declined during test period. After 240 d immersion test, minor pitting appeared on non-shaped sample surface, the pitting density of 45° deformation sample surface increased, and 90° deformation sample surface had cracks perpendicular to the direction of stress. XRD results showed that the adsorption of Ca2+ and Mg2+ ion increased at the deformation, which may be related to the surface roughness and surface activity of TC2 titanium alloy increase. In simulated seawater, the non-shaped TC2 titanium alloy has strong anti-corrosion properties and strain causes breakage, pitting and even cracks on passive film of TC2 titanium alloy, thus increasing stress corrosion sensitivity of TC2 titanium alloy.