In view of the current situation that there is no consensus on the determination method of damping ratio at home and abroad, this paper takes Fujian standard sand (particle size 0.5~1.0mm) as the test object, using undrained stress control dynamic triaxial test to analysis. The existing methods including traditional method, Das and Luo method, Kokusho method, Kumar method, cross-correlation function method for determining damping ratio are comparatively analyzed , and the differences between them is evaluated. The results show: in general, the damping ratio determined by the five damping ratio determination methods are quite different. The damping ratio determined by Kumar method is closest to the average damping ratio, the damping ratio determined by the cross-correlation function method is much higher than the average damping ratio, the damping ratio determined by Das and Luo method and Kokusho method is basically the same but lower than the average damping ratio. The damping ratio determined by the traditional method is much lower than the average damping ratio. It is recommended that in future engineering applications, when the loading method is stress control, the Kumar method can be used to determine damping ratio.