According to the problems of stratum broken, uneven rock hardness, serious drilling mud leakage, low drilling efficiency and difficult coring in Sanhe coal mine goaf subsidence area of Hebei, a series of drilling technical methods were adopted to improve drilling efficiency on the premise of ensuring the quality of core drilling engineering. The accurate and detailed geological data are provided for preliminarily ascertaining the scope of ground subsidence of Sanhe coal mining area, the development characteristics and harm degree, which can be the basis for the development and utilization of coal mine goaf subsidence area and the next exploration and urban & rural planning.