Abstract: Split Hopkinson pressure bar (SHPB) system was used to investigate the dynamic compressive properties of in situ synthesized TiC particles and TiB whisker mixing reinforced titanium matrix composites (TMCs) at the temperature range 293-973 K and the strain rates range 6 000-10 000 s^-1. The test results show that the flow stress of TMCs significantly decreases with the temperature increasing when the temperature is in the range of 373-573 K, 673-773 K and 873-973 K. At relatively low temperature (lower than 373 K) and low strain rate (6 000-8 000 s^-1), TMCs exhibit a slight strain rate hardening characteristic. However, at high temperature (573 K or higher), TMCs present obvious strain softening feature at all strain rates used and the strain rate softening effect is more significant under higher temperature. The analysis on the failure/fracture mechanisms shows that the combined effect of the adiabatic softening and the behavior of the micro cracks generation and development in the adiabatic shear band (ABS) are the mechanisms for the strain softening. Under high strain rate combined with high strain, micro cracks initiate in the ABS and will cause the rapidly damage or fracture of TMCs on the macro when the ductility of the TMCs is not high enough to suppress or hinder the development of the micro cracks under relative low temperature. Titanium alloy matrix plastic fracture is the main material damage mode but local brittle fracture also presents around the reinforcement phase.