The hot deformation behaviors of TC11 alloy were investigated at temperature range of 800~1050 ℃ and strain rate range of 0.005~5 s-1. Based on dynamic materials modeling (DMM) the processing map was established. Combined with the microstructure observation the hot deformation mechanism of TC11 alloy was worked out. The results show that the globularization of lamella α is the main deformation mechanism at low strain rate (0.005~0.05 s-1) in the (α+β) phase field. The globularization intensities increasing obviously with decreasing of temperature and increasing of strain rate. The unstable flowing will occur at high strain rate (0.05~5 s-1), and shear crack and shear bands will take place. In the β phase field, the dynamic recrystallization occurs at low strain rate (0.005~0.05 s-1) and the dynamic recovery occurs at high strain rate (0.05~5 s-1). Furthermore, the flow instability maybe occur when the strain rate is higher than 0.1 s-1. The peak efficiency of power dissipation of about 57% is obtained at about 900 ℃ and 0.005 s-1.