Thin wall samples from TA12 titanium alloy have been prepared on TA15 substrates by laser direct deposition of coaxially fed metallic powders under protective gas. The microstructure,phases and mechanical properties of the deposited materials were investigated. The results indicated that the deposited materials are fully dense,and metallurgically bonded with the substrate. The as-deposited TA12 titanium alloy tendes to be equiaxed grains,within which is basketweave widmannstatten structure formed of many fine α lamella and small amount of β with different direction. And the size of the original β-Ti grains increases a little with increasing the laser power used for depositing. The tensile strength at room temperature and under 550 ℃ for the as-deposited materials along the scanning direction reaches the value for the annealed bar.