Abstract: Different seismic loads have important effect on loess subsidence. By means of the triaxial testing equipment, which is used to load random waves on specimen axially, undisturbed loess subsidence is comparatively studied under different seismic loads, and the effect of different seismic load on characters of loess subsidence is analyzed. The test indicates that the rasidual deformation of loess increases with the increase of dynamic stress under random seismic load or sine wave load, but the increase tendencies of them are different, which show that the characters of loess subsidence vary obviously under different seismic loads, and the effect of different seismic loads on the critical dynamic stress of loess subsidence is different, that is the critical dynamic stress is larger under the random seismic load than under sine wave load, and the effect of the random seismic load with different predominant periods, peaks and durations is also different, that is, the loess subsidence has relation with the predominant period, peak and duration of the random seismic load, and the effect of the predominant period is quite obvious.