Abstract: Filling effect is an important indicator of goaf treatment evaluation. In order to study the applicability of geophysical methods in goaf filling treatment effect evaluation, this paper takes a concealed goaf in a closed pit iron mine in Zibo City as the research object, and applies controlled source audio-frequency magnetotelluric method and fretting measurement to observe time-shift data. By normalizing and standardizing the measurement data of goaf, the electrical characteristics and elastic wave velocity characteristics and differences before and after goaf filling are analyzed, and a technical method suitable for goaf filling effect evaluation is proposed. The results show that the interpretation results of controlled source audio-frequency magnetotelluric method can reflect the range of water-filled goaf and its water filling channel, in which the water-filled goaf is a closed low-resistance abnormal area, and the low-resistance strip abnormal caused by water filling channel is related to the water-rich fissure zone. The interpretation results of fretting measurement can clearly reflect the range of low-speed abnormal caused by water-filled goaf, but the water filling channel is not obvious. Both of the two geophysical methods have good application effect in the range detection of goaf. Affected by the goaf water filling, the goaf before and after filling treatment exhibited the characteristics of low resistance and low velocity anomalies, but the difference of elastic wave velocity characteristics is more obvious than that of electrical characteristics, and the abnormal resolution is clearer. The applicability of fretting measurement method in the evaluation of goaf filling treatment effect is better than that of controlled source audio-frequency magnetotelluric method.