The occurrence of most sandstone type ore bodies mined by in-situ leaching uranium mining technology in China is relatively gentle, and the dip angle of ore bodies is generally less than 10°.How to carry out in-situ leaching mining for sandstone type ore body with large dip angle(greater than 15°) is an important research content of in-situ leaching uranium mining technology.Some areas of the main ore body of Qianjiadianqian block II uranium deposit in Inner Mongolia are affected by geological faults, and the dip angle of the ore body reaches 25°, which poses a difficult problem for in-situ leaching mining.In the mining process, by optimizing the well layout and adding injection wells in the direction of ore body strike, the balance between pumping and injection in the leaching process is realized.The well spacing of pumping and injection wells in the dip direction of the ore body is 30 m, which can reasonably control the leaching agent migration time and achieve a higher leaching rate.Precise selection of target ore block, precise design of drilling filter position, and accurate mining of ore body.The effective leaching of uranium ore body resources has been realized by reasonably regulating the production and operation parameters and optimizing the preparation parameters of leachant.Affected by the large dip angle of the ore body, accurately grasping the movement path of the leaching agent in the ore bearing aquifer is a necessary technology for further mastering the in-situ leaching of the ore body with large dip angle.It is suggested that the tracer technology be used to track the movement path of the leaching agent in the ore bearing aquifer in the subsequent operation to determine the movement range of the leaching agent, provide a basis for optimizing the well type and spacing layout, and provide a reference for the mining of such uranium ore bodies.