Abstract: By embedding a "guide wave sensor" composed of waveguide rod and steel balls inside the tailings dam model, the relationship between the characteristics of dam failure process and the evolution law of guided waves was studied, and the guided wave technology was verified Feasibility for safety monitoring of tailings dams. The ringing parameters in different stages of dam break had different characteristics, and the ringing val" can be regarded as a precursor of slip failure. Guided wave ringing parameter sequence had significant fractal characteristics, the evolution model of fractal curve was "rising-falling", which reaches the maximum value during dam slip period. During the test, the dominant frequency of the guided wave was mainly located in two frequency bands, and an "abnormal" dominant frequency signal will appear during the micro-crack propagation and penetration stage.