In this paper， the subsidence deformation processing of the thin-walled TC2 alloy profile was studied by thermal tensile tests and computer simulations. First， the hot tensile deformation behavior of the TC2 alloy profile was analyzed in the temperature range from room temperature to 600 ℃. Then， Johnson-Cook constitutive model was used to describe the hot tensile deformation behavior. Through computer simulations， the distributions of stress and stress triaxiality during subsidence deformation were analyzed. The results show that stress concentration is easy to occur at the corner of L in the subsidence area， and it is tensile stress due to the stress triaxial R_d＞0 of the area before deformation. With the increasing deformation， the crack extends in lengthwise direction of the profile. By optimizing the forming temperature， the length of the subsidence area and the transition radius， the best subsidence deformation processing parameters for the TC2 alloy profile are deformation temperature is 300 ℃， length of subsidence deformation zone is 21 mm， interim fillet radius is 49 mm.