The dynamic shear modulus and damping ratio are important parameters in earthquake engineering and other dynamic analyses. In this paper, the experimental research on dynamic shear modulus and damping ratio of loess with the DJC-240 triaxial test apparatus was introduced by statistic method and the accuracy of the parameters was improved. The revisionary formula for calculating dynamic shear modulus based on physical properties of soil was presented. The authors have pointed out the obvious influence of damping ratio due to different consolidation ratio and consolidation pressure. The essential correlation between damping ratio and the construction of loess was found.