The structural property of soil is derived from mechanical effects as well as the comprehensive effect of the spatial arrangement and bonding effects of soil particles. During the process of seismic loads, the structural parameters of natural loess slope are derived mainly from the combined effects of stress and deformation. Meanwhile, that parameters reflected the coordination between stress and deformation during the process of seismic load and the structural damage process of the loess during the seismic process. It was shown that using structural parameters to quantitatively determine the loess slope stability was more reasonable during the process, and its physical meaning was very clear. Second, analysis of the dynamic stability of the natural loess slope was used to verify the feasibility criterion by structural parameters, and this method could be used to quantitatively determine the location of slip surfaces and corresponding structural parameters.