In this paper, the dynamic mechanical properties and failure behavior of rolled and heat treated Ti-4.5Mo-5.1Al-1.8Zr-1.1Sn-2.5Cr-2.9Zn alloys were studied. After multi-pass rolled at 880℃, a duplex microstructure consisting of β matrix and non-uniformly distributed _^-1~3800s_^-1 show that the dynamic compression strength of rolled titanium alloys is about 200MPa~400MPa higher than that of heat treated titanium alloys, with a maximum value of 2133MPa, but the critical fracture strain is obviously lower, with a maximum value of only 10.8%. Although the dynamic compression strength of titanium alloys decreases after heat treated, the critical fracture strain can reach 23.6%, showing better matching feature of strength and plasticity. Further study found that the characteristic of high dislocation density and inhomogeneous structure distribution of rolled titanium alloys result in bifurcated adiabatic shear bands during dynamic compression tests. The fracture surfaces of rolled titanium alloys show two characteristics: smooth zone and dimple zone, indicating that the fracture mechanism is brittle fracture + ductile fracture, while that of heat treated titanium alloys is mainly dimple zone, indicating that the fracture mechanism is ductile fracture. The research provides theoretical and technical support for the engineering preparation and application of the new alloy.