Abstract：Some aspects such as the behaviors of pore pressure，dynamic strength，and dynamic deformation of unsaturated loess are studied with the dynamic torsional shear test of loess. The pore air pressure gradually rises with the development of axial strain in the process of the dynamic torsional shear test of loess，but the pore water pressure essentially keeps constant or goes up a little in the latter stage. There are some considerable differences in strength and strain between unsaturated loess and saturated loess. The effects of water content，consolidation pressure，and consolidation pressure ratio on the dynamic characteristics of loess are also analyzed.
