Abstract: The hot compression deformation behavior of 2219 aluminum alloy fabricated by TIG additive manufacturing was studied by Gleeble-3500 thermal simulator. The high temperature uniaxial compression tests were carried out at the strain rates of 0.01, 0.10, 1.00 and 10.00 s^-1 in the temperature range of 200-500 ℃, and the true stress-strain curves under the corresponding conditions were obtained. The results show that the peak stress range of 2219 aluminum alloy fabricated by TIG additive manufacturing is 21-260 MPa. The main softening mechanism of the material during high temperature compression is dynamic recovery, supplemented by dynamic recrystallization. The average grain size decreases with the increase of strain.When the deformation reaches 60%, the grains are basically broken and seriously distorted. The increase of temperature promotes dynamic recovery. At 500 ℃ and strain rate of 0.01 s^-1, the grain refinement caused by deformation is offset, and the grains are all equiaxed without distortion. A constitutive model for deposited materials is established to reflect the rheological stress of the material under compression conditions, providing a theoretical basis and data for the numerical simulation and optimization of the WAAM composite process of 2219 aluminum alloy during hot synchronous rolling.