The dynamic properties of frozen soil are closely related to the designing， operating， and maintaining of many infrastructure projects in permafrost areas. The dynamic parameters of permafrost are obtained from the hysteretic curve of frozen soil. Therefore， a comprehensive investigation of the morphological characteristics of frozen soil hysteretic curves is important to clarify the dynamics of frozen soil and its influencing factors. The morphological characteristics of the hysteretic curve of frozen soil can be described by four parameters： the axial dynamic stress amplitude， the degree of non-closure， the width and the area of the hysteretic curve. The specific dynamic characteristics of frozen soil reflected by these four parameters are as follows： the curve enclosed by axial dynamic stress amplitude and dynamic strain amplitude of frozen soil is called the backbone curve， which reflects the magnitude of equivalent deformation， nonlinear effect， and dynamic elastic properties of frozen soil； the degree of non-closure of frozen soil hysteretic curve reflects the plastic deformation property of frozen soil； the width of the frozen soil hysteretic curve reflects the viscous hysteretic property of frozen soil； the area of the frozen soil hysteretic curve reflects the energy dissipation capacity of frozen soil. To this end， a negative temperature dynamic triaxial test was carried out on silty clay in the seasonally frozen soil area of Northwest China. The experiment included ten testing conditions， which composed of four soil temperatures （-0.3 ℃， -1 ℃， -3 ℃， -5 ℃）， three soil water contents （14%， 16%， 18%）， three confining pressures （0.1 MPa， 0.2 MPa， 0.3 MPa） and three loading frequencies （1 Hz， 2 Hz， 4 Hz）. According to the test results， the variation trends of four morphological characteristic parameters describing hysteretic curves with vibration cycle number， confining pressure， soil temperature， water content， loading frequency， and dynamic strain amplitude are analyzed. The results show that the effect of vibration cycle number on the morphological characteristics of the hysteresis curves of frozen silty clay is small. With increasing the dynamic strain amplitude， the growing mode of the backbone curve of frozen silty clay gradually changes from an approximate linear mode to an obvious nonlinear mode. And the degree of no-closure and area of the hysteretic curve increase in a concave curve shape， while the width increases in a convex curve shape. With the increase of confining pressure， water content， loading frequency and the decrease of temperature， the backbone curve of frozen silty clay become steeper and the nonlinear effect is weaker， while the degree of no-closure， the width and area of the hysteretic curve tend to decrease in varying degrees. When the confining pressure is below 0.2 MPa， the water content is below 16% and the temperature is below -3 ℃， the morphological characteristics of the hysteretic curve of frozen silty clay change more obviously with these factors. The degree of non-closure and width of the hysteretic curve is more balanced by the loading frequency， and there is no optimal influence range. Among the four influencing factors， loading frequency and soil temperature have a greater influence on the area of the hysteretic curve， and the water content has the latter influence， while the overall influence of the confining pressure on the area of the hysteretic curve is small. The area of hysteretic curve-dynamic strain amplitude relationship curves of frozen silty clay under the three kinds of confining pressure used in this test almost coincide.