Abstract: Dynamic elastic modulus and damping ratio are the basic mechanical parameters for dynamic analysis of soils, which can be usually got by dynamic triaxial tests with small strain range. The reliability of test technology and the accuracy of the test parameters are the key to the aseismic safety assessment. Based on the results of the dynamic triaxial tests, the influences of several factors such as using internal or external sensors, relative position of force and displacement sensors on the hysteresis loop, dynamic elastic modulus and damping ratio are analyzed. A new method is proposed, which can be used to calculate the dynamic modulus and damping ratio when there is non-closed hysteresis loop of residual deformation, and the influence laws of the frequency, confining pressure, consolidation ratio and other factors on the test results and their characteristics are compared. The influence factor of power function is also added to the Janbu formula, and the normalized characteristics of dynamic elastic modulus and damping ratio with different confining pressures and consolidation ratios are studied. The research results will help improve the ability of domestic research institutions to test the dynamic parameters of soils, and this study also has a positive reference significance to the antiseismic engineering and scientific research.