Pumping test is one of the effective measures to acquire the hydrogeological parameters of groundwater aquifers. In order to accurately grasp the aquifers characteristics and hydraulic connection, this paper studied the watery of main mining coal seams,he hydrogeological characteristics of the aquifers and the hydraulic connection by applying the pumping tests, theoretical analysis and water quality tests on the Balasu well field. The results show that the watery of the No.2，No.3 and No.8 coal seamsare all weak. Except the wateiy of the Quaternary system aquiferis medium - strong and the Cretaceous system Luohe group aquiferis medium,the watery of the other aquifers are weak. The Quaternary system aquifer is closely related to the Cretaceous system Luohe group aquifer, and there are no hydraulic connection between the Cretaceous system Luohe group aquifer and the Jurassic system Zhiluo group aquifer, and between the Jurassic system Zhiluo group aquifer and the No.2 coal seam, and between the No.3 and No.8 coal seam respectively. The results of the pumping tests will provide a strong theoretical basis for the future hydrogeology and prevention and control of water hazards in the coal mine, and also render reference for the surrounding coal mines with the similar conditions.