Abstract: Using model experiment, in the condition that the sliding force unchanged, the internal cohesive force and friction force of the slope were analyzed by the natural vibration frequency. The stabilization of landslides was decided by comparing the friction force with the maximum static friction force in the weak stable phase. Experimental results show that the friction force can effectively analyze the safety of landslides in the weak stable phase and that the natural vibration frequency is more sensitive than the displacement. By monitoring the natural vibration frequency, a quantitative assessment about the damage of landslides can be made, which provide the static friction force index, and the safety assessment of landslides after disturbances is achieved.