Abstract: The mechanism of laser cleaning process of titanium alloy was analyzed, and the laser cleaning technology of marine TA5 titanium alloy was studied.The surface morphology and chemical composition of TA5 titanium alloy under three states of surface oil, acetone cleaning and laser cleaning were compared and analyzed.The laser cleaning effect of TA5 titanium alloy welded joint with three different oxidation degrees of yellow, blue and purple on the weld surface was studied.The microstructure, tensile strength and bending properties of TA5 titanium alloy welded joint were investigated under laser cleaning condition before welding.The results show that, the laser cleaning effect of titanium alloy is obvious, it can effectively remove the impurities pollutants and oxide layer, the effect is better than acetone cleaning.After laser cleaning, the three kinds of welds are silver white, and the oxygen content on the weld surface is between 8.26wt%and 8.65wt%, and the weld surface quality is basically the same after laser cleaning.The weld zone of the joint is characterized by acicular α and jagged α phase, and the heat affected zone is characterized by isometric α, acicular α and jagged α phase.The average tensile strength of the joint is 767 MPa, which is higher than that of the base metal, and the joint breaks at the base metal.The joint has good bending performance.The laser cleaning of titanium alloy has a good application prospect in engineering.