Abstract: Collapsed column is one of the main factors influencing coal mining and CBM development. Study on the origin and characteristics of the collapsed column in coal seam helps to reduce the investment risk in coal mining and CBM development. On the basis of the analysis of the control factors and development features of the collapsed column, combined with the distribution of the collapsed column in Wangpo coal mine, the effect mechanism on CBM distribution and development is studied. The gas content of seam No.3 is low around the collapsed column, and because the collapsed column may connect the Ordovician strata and coal seam, the collapsed column has an adverse effect on the drilling, the fracturing and the drainage engineering in CBM development.