Abstract: Identifying the spatial distribution characteristics of old goaf is essential to prevent and control of surface collapse disaster of goaf. Aiming at the problem that the existing detection accuracy is still difficult to meet the needs of goaf management, a detailed detection method of goaf is proposed,that is,high precision magnetic method detecting the plane range of goaf,natural source surface wave method and controlled source audio magneto telluric method measuring the position of goaf, exploration drilling modifying the detection results. Taking Dunqiu Iron Mine as an engineering background,high precision magnetic method is used to detect the characteristics of magnetic field,and the plane distribution range of old goaf is delineated. Further,natural source surface wave method and controlled source audio magneto telluric method are used to measure the strata section,the resistivity and wave velocity of rock in different positions are obtained,the vertical distribution range and depth of goaf are inferred,which are contrasted and modified according to the results of exploration drilling finally. The detailed detection on spatial distribution of goaf in iron mine is realized. The plane shape of goaf formed by the mining of No. 2 orebody group is approximately crooked gourd shape,with an area of 4 992. 5 m2. The goaf can be divided into pure goaf and backfill goaf. The goaf volume of No. 2 orebody group is 112 281. 33 m3,which is calculated by the average thickness method. The detection results are in good agreement with the basic mining data,and the research methods and results have certain guiding significance for the detection and treatment of old goaf in iron mine.