The dynamic mechanical properties of equiaxed microstructures of four TC4 titanium alloys were studied with Split Hopkinson pressure bar device under the strain rates 2000, 3000 and 4000 s-1. Curves of dynamic stress-strain under different conditions were obtained. The results show that the dynamic strength, dynamic strain and absorbed energy of equiaxed microstructures of four TC4 titanium alloys all increase with the increasing content of Al and V. The dynamic mechanical properties have been improved. With the increase of interstitial elements content, the dynamic strength and the absorbed energy of the equiaxed microstructure increase while the dynamic strain decreases.