Abstract: In Huainan coal mining area (HCMA),the large scale coal mining causes a wide range of ground subsid- ence and affects the sustainable development of local economy. Based on the field investigations,the prediction tech- nology of mining subsidence and theoretical analysis,and combined with the favorable factors,the authors propose that a reservoir can be built using the mining subsidence area in HCMA. The results show that before 2010,the area of ground subsidence in HCMA is up to 121. 4 km2 which includes a water area of 59. 8 km2 . According to forecasts,be- fore 2020,the subsidence area and water area will reach 186. 9 km2 and 112. 7 km2 respectively. After 2030,the sub- sidence area will be 275. 2 km2 ,and the water area will be 195. 4 km2 . Numerous river systems and natural depres- sions are distributed around the HCMA,and they connect to the mainstream of Huai River through sluice gates of riv- ers and lakes (i. e. Huajia Lake and Xifei River).