Abstract: The value of strength reduction ratio is a key issue in the slope stability analysis by using double factors strength reduction technique (DDRM). By considering the nonsynchronous shear strength deterioration of the internal friction angle φ and the cohesive strength c, the dynamic proportional relation of the strength reduction factor F_φ/F_c is proposed in this paper. Moreover, based on a comprehensive factor of safety by the shortest path method of the strength reduction technique and the minimum value principle of the slope factor of safety, this paper presents a slope stability analysis method by the DDRM. The results indicate that the slope safety curves which can be fitted well by the polymerization with above 0.99 fit degree show an obvious nonlinear characteristic. The curve of the c-F_φ/F_c indicates that the strength reduction factor ratio F_φ/F_c  is varied between 1.02 and 1.09 which verify the rationality of the DDRM. Comparing with the traditional single factor (SRM) and the double factors strength reduction technique (DRM), the value of the strength reduction factors F_φ/F_c is simpler and the dynamically changes by the DDRM proposed in this paper. So, the smaller slope factor of safety by the DDRM makes the slope safer and the factor of safety is more reasonable than by using both the SRM and the DRM.