The water hazard hided in strata separation cell is one of unusual and dangerous hazards in coal mines.The causes of water hazard happened in Haizi coal mine,Huaibei Coal Mining Inc.was investigated by hydrogeological and geotechnical analyses,physical analogue,numerical simulation and water slug tests.The responding draining measure was taken to control the water hazards and the tests were successful.The achievements can be applied to the working faces with the similar hydrogeological condition to guarantee mining safe.