The effect of different laser power on the joint formation, weld morphology, and microstructure of TC4 titanium alloy were studied by laser-tungsten inert gas (TIG) hybrid welding process. The results show that TC4 titanium alloy welded by laser-TIG hybrid welding can form a welded joint with good surface shape, and no obvious defects such as undercut and overlap. The molten pool near the laser beam will produce violent flow, and there will be pits at the center of the weld surface after the molten pool solidifies. With the increase of laser power, the cross section of the weld gradually changes from “mushroom” shape to “hourglass” shape, the average pore area gradually decreases, and the pores are mainly concentrated at the bottom of the weld. Under the hybrid of laser-TIG, the increased laser power will make the molten pool flow more intense and the grain size will gradually decrease. The microstructure of the weld is α′ Martensite bundles composed of multiple parallel α′ Martensitic with narrow residues β Phase band. The width of the β phase band varies considerably, the wider area is about 1.95 μm, and the narrow area is about 0.45 μm.