Abstract: The water filling source is the sandstone aquifer on the roof in the mining face in muduchaideng coal mine which is analyzed in this paper. The permeability coefficient is obtained by the underground dewatering test. On this basis, the drainage water yield in the first mining face is calculated by the principle of superposition of the interference well group. According to the result, the final arrangement of the the roof water drainage drilling field is determined. It provides a new way of calculating the drainage water yield in the first mining face and a valuable reference value for calculating the drainage water yield of the surrounding mine.

Key words: the interference well group, the principle of superposition, the first mining face, the drainage water yield