Abstract: Dafosi Coal Mine is located in the south of Binchang Mining Area, the roof of the main coal seam is covered with a huge thick Luohe Formation aquifer, 4 coal mining, and the water-conducting fracture zone links to the Luohe Formation aquifer, which has become the main water-filled aquifer of the coal mine, therefore, it is necessary to understand the water-rich mechanism of the Luohe Formation aquifer.In this paper, through X-ray diffraction, CT scan, nuclear magnetic resonance and other experiments, we have found that the sandstone types of Luohe Formation are mainly lithic feldspar sandstone and feldspathic sandstone.The particle size is mainly fine sand and medium sand, and the particles are transitional supports, which are well sorted, and most of them are sub-circular, mainly pore cementation.The pore types were divided into three categories, from class Ⅰ～Ⅲ,the pore radius and permeability decreased sequentially.The aquifer of the Luohe Formation is rich in static reserves with good recharge conditions and large water column height, and there is no watershed around the well field, so the aquifer dredging is not feasible.The results of this analysis explain the water-rich mechanism of the aquifer of Luohe Formation from a microscopic perspective.