Laser self-fusion welding experiments were performed on the novel Ti–3773 alloy. The welding performance, mechanical properties, and corrosion resistance were investigated by X-ray diffraction (XRD), optical microscopy (OM), scanning electron microscopy (SEM), hardness tester, universal tensile testing machine, and potentiodynamic polarization measurement. The results showed that the optimum welding parameter ranges for the novel Ti–3773 alloy are as follows: Welding powers of 2300 W, 2400 W, and 2500 W with a welding speed of 10 mm/s; welding powers of 2600 W, 2700 W, and 2800 W with a welding speed of 14 mm/s. Under the optimum welding process conditions, the weld center of Ti–3773 alloy consisted of a single phase of coarse β grains, while the heat-affected zone was composed of fine β grains and a small amount of dispersed α phase. The average tensile strength and elongation of the welded joint were 71.38% and 265.67% of those of the base metal, respectively, indicating that the welded joint exhibits superior plastic deformation capacity. The hardness of the heat-affected zone reaches the highest value, which is attributed to finegrain strengthening induced by refined β grains and precipitation strengthening from α phase precipitation. The corrosion resistance of the heat-affected zone is the worst, with a corrosion current density of 3.6191×10–7 A/cm². After welding, the corrosion resistance of different zones of the Ti–3773 alloy follows the order: Base metal>weld zone >heat-affected zone.