The effect of marine environment on fracture toughness for TA15 titanium alloy was studied by marine platform outdoor exposure test and marine splashing test. The results show that the fracture toughness for TA15 titanium alloy decreases with increasing marine atmosphere environment test time. The effect of marine splashing test for fracture toughness is bigger than marine platform outdoor exposure test. The fracture toughness of TA15 decreases 10. 4% after 4 year爷s marine splashing test,the embrittlement increases by fracture morphology analysis. The near surface effects were discussed by XPS,most likely to be the diffusion of oxygen into the alloy.