Abstract: A new laser-TIG(laser beam and tungsten inert gas) hybrid welding procedure for titanium alloy T-joint structure called single pass welding and double backside shaping technology is proposed.The forming properties of the T-joint structure is analyzed and discussed under different testing conditions by a series comparative welding experiments to reveal the optimal scheme of single pass welding and double backside shaping with laser-TIG hybrid welding for titanium alloy T-joint structure.The results indicate that comparing with the TIG melt through welding methods,the proposed single pass welding and double backside shaping technology based on laser-TIG hybrid welding procedure for titanium alloy T-joint structure is obviously advantageous in weld forming,weld microstructure,weld composition,weld property,welding efficiency and the tolerance to gaps between plates.