Abstract:Titanium and its alloys, characterized by light weight, excellent corrosion resistance, high strength, low elastic modulus, superior biocompatibility, and outstanding osseointegration, have become one of the mostly widely used metallic materials in aerospace and biomedical fields. However, their relatively low plasticity, hardness, and wear resistance constrain further development and applications. Laser surface treatment (LST) technology, which enhances surface properties without altering the bulk material, has emerged as a beneficial approach to modify the surface of titanium alloys. The research advancements and current applications of LST in surface modification of titanium and its alloys were reviewed. The mechanisms, process parameters, surface characteristics, and microstructures of various LST methods were analyzed, including laser transformation hardening (LTH), laser surface remelting (LSR), laser shock peening (LSP), laser surface alloying (LSA), laser cladding (LC), and composite LST techniques. The applications of LST in aerospace and medical domains were also clarified, as well as existing limitations, future research directions, and insights into the developmental trends of LST for titanium and its alloy materials. The objective is to advance LST innovation and to pave new avenues for the application of titanium alloys in various sectors.