Abstract: The high temperature compression tests of furnace cooling state TA15 titanium alloy were carried on Thermecmastor-Z simulator in the temperature range of 750-950 ℃ and strain rate range of 0.001-10 s-1.The influences of strain rate and temperature on the flow stress and microstructure of the alloy were studied.The results show with the increase of temperature and decrease of strain rate,the flow stress of the alloy decreased,the α-phase content also decreased,deferences between the α-phase in grain and along the boundary disappeared,and part α-phase occured nodularization.The optimum forging parameters for TA15 titanium alloy were in the temperature range of 850-950 ℃ and strain rate range of 0.001-0.01 s-1.