A method of determing the maximum epicentral distance of seismic landslide and the maximum fault distance of seismic landslide is proposed through analysis on data of seismic landslide disasters in Shaanxi-Gansu-Ningxia-Shanxi loess region.Some nonlinear fitting calculations were carried out and a preliminary mathematical relationship between the magnitude 5.5≤M_S≤8.0 of earthquakes and both the maximum distances is developed.Furthermore,the main factors of affecting the seismic landslide disasters are discussed in order to study accurately this relationship for different areas.