Old goaf water disaster is the main type of water disaster in deep mining of integrated mine. Accurately grasping the distribution and amount of water accumulation in goaf is the premise of accurate exploration and discharge. Taking Heilongguan Coal Industry Co., Ltd., Puxian County, Shanxi Lu 'an Group as the research object, based on the systematic analysis of mine geological and hydrogeological conditions, the water outburst threat of the overlying No.2 coal seam goaf water to the underlying No.9+10+11 coal seam mining was clarified. Based on the ' horizontal two vertical three ' partition water control mode, the water accumulation in the goaf was divided horizontally into the insufficient water accumulation area of coal pillar support and the middle compacted water-resisting area, and it was divided vertically into the bottom compacted water-resisting area, the middle water storage area and the upper recharge area, which revealed the enrichment law of water accumulation in the goaf. The 3DMine three-dimensional mining software platform was used to construct the mining area exploration database and the three-dimensional solid model of the old goaf. Through the spatial superposition of the groundwater level surface and the old goaf floor, the three-dimensional entity of the water accumulation body was generated. Combined with the correction of the water filling coefficient, the accurate calculation of the water accumulation in the old goaf was realized. The results showed that there were 12 water accumulations in the old goaf of No.2 coal seam in the mine field, with a total area of 587 895 m2 of water accumulated area. The water accumulation calculated by the three-dimensional model volume method was 243 030 m3, the relative error of which was less than 1.4 % to the traditional empirical formula method ( 246 400 m3 ). However, the empirical formula method had a large error in a single water accumulation area because the dynamic change of porosity after overburden collapse and compaction was not considered. The three-dimensional water accumulation model and volume method proposed in this study could provide technical reference for the prediction of old goaf water accumulation under similar conditions.