A series of studies on dynamic elasticity modulus and damping ratio of highly weathered rock which covered by loess are conducted with small strain εd, using triaxial shear equipment and their dynamics properties are analyzed. The results show that the dynamic stress and strain relation of highly weathered rock is nonlinear elastic relations, and fit the model of hyperbolic type with small strain εd. Within the same strain range, the mudstone’s damping ratio is greater than the red sandstone’s. In the same consolidation condition, the initial elastic modulus of red sandstone is greater than the one of mudstone. The research provides experimental technology and dynamic property parameters to dynamic response analysis and seismic deformation mechanism study for highly weathered rock which covered by thick layer of loess.