Abstract: In order to explore the development rule of water-conducting fracture zone in fully-mechanized coal face and provide important reference for the prevention and control of coal mine roof water damage, the development height of water-conducting fracture zone in 9105 fully-mechanized coal face of Gaizhou coal Mine was studied by traditional empirical formula calculation, software numerical simulation and borehole peeping technology, and mutual verification was conducted. The results show that the development height of the water-conducting fracture zone determined by borehole peeping technique is more accurate, but it is greatly affected by the highest saddle-shaped position and observation time of the overburden after mining. Height correction using borehole trajectory analysis is the key to improve borehole peeping technique to determine the height of water-conducting fracture zone. The closer the dip Angle and bearing of borehole are to the design parameters, the more accurate the prediction of the development height of water-conducting fracture zone will be. It can be seen that the combination of borehole peeping technology with traditional empirical formula and numerical simulation technology to determine the development height of water-conducting fracture zone is an effective means to improve the quantitative evaluation of the development height of water-conducting fracture zone.