A suspected collapsed coal column abnormal area was found by 3 d seismic exploration in No. 8 mining area of Longgu Coalfield. Kinds of exploration and property demonstration of collapsed coal column was conducted by drilling exploration, 3 d seismic method and electrical prospection, drilling exploration with normal coal seam and standard seam but some broken stratum, no Karst cave or cave formation within Ordovician limestone 100 m, with normal water richness of various aquifer. The abnormal area was analyzed as blocks of untypical collapsed coal column, with low coal seam collapse height, normal strata, poor water conductivity, without obvious connection between three sand aquifer and Ordovician limestone, which has little threat to water threat in mining. The detection result guided safe mining and design of the area.