Abstract: In order to find out the hydrogeological characteristics of Baotashan sandstone aquifer in Jurassic coalfield on the basis of pumping test, underground dewatering test was used adopted. The everage water drainage value of single-borehole was 237.91 m³/h, the average water drainage value of multi-borehole was 444.10 m³/h, and the maximum ground water drawdown of Baotashan sandstone aquifer was 310 m. The permeability coefficient and unit water inflow of aquifer were calculated by means of the dewatering test with large flow and drawdown, it was confirmed that there were hydraulic connections between Baotashan sandstone aquifer and cretaceous, coal measures and triassic aquifer. The influence range of dewatering test and the drawdown law of observation borehole were investigated, it was proved that Baotashan sandstone aquifer can be drainaged. Based on the hydrogeological characteristics of Baotashan sandstone aquifer, the prevention and control scheme of floor sandstone water disaster from bottom sandstone with lower coal mining group was put forward. The results show that the dewatering test with large flow can stimulate the groundwater drawdown to the greatest degree, and effectively make up for the inadequacy of the surface pumping test. The research results of hydraulic connection among each aquifer, the influence scope of groundwater drainage and the drainage possibility of aquifer can be used as the basis for the prevention and control of sandstone water disaster in mine floor.