Abstract: Aiming at the difficult problem of water accumulation in goaf of coal seam roof threatening the safe stoping of working faces, this research takes the 5108 working face overlying 2^# coal seam goaf of Yushupo Coal Industry in Ningwu, Shanxi Province as the research object, it proposes to adopt mine transient electromagnetic method (TEM) to conduct drainage water engineering dynamic monitoring. 103 measuring points are set up in the inlet and return air crossheadings and cutting holes of the 5108 working face, by quantitatively comparing the detection data before and after drainage water, combined with drilling verification and hydrogeological data, the drainage effect of water accumulation in the goaf is systematically analyzed. The results show that four low resistance abnormal areas (CKJS1, CKJS3, YC1, YC2, with a positioning accuracy of ± 8 m) are delineated with an apparent resistivity threshold of <15 Ω·m before drainage water; After drilling verification of drainage water, the abnormality completely disappeared after 1745 m³ of water volume is drained in CKJS1 area, and the overall apparent resistivity is improved by 63% (the average value is increased from 12.8 Ω·m to 20.9 Ω·m). The drainage water engineering significantly changes the electrical property differences in the roof goaf. The mine transient electromagnetic method can achieve dynamic monitoring of the spatial distribution and drainage of water accumulation in the goaf, providing a real-time technical decision-making basis for water hazard prevention and control.