In order to further solve the development and utilization of coal bed methane in the Shanxi Jincheng mining area， coalbed methane in the lower goaf of the 3^# coal seam should be properly and effectively exploited and utilized to reduce the content of gas in the coal seam so as to ensure the efficient and rational use of coalbed methane， and provide safety guarantee for coal mining. This paper studies drilling technology for CBM horizontal wells through goafs in this area with the drilling process with DTH hammer and air PDM plus nitrogen put forward. With optimization of the well structure， the construction problems such as collapse， falling blocks and leakage in sensitive stratum in goafs were effectively solved. The smooth completion of coal-bed methane horizontal wells through goafs has verified the feasibility of the drilling technology， can provide guide for the coming large-scale development of coalbed methane.