Abstract: The groundwater numerical simulation and particle tracking method were used to analyze the plane distribution characteristics of the solution flow rate of the " horizontal well injection-vertical well pumping" well pattern in in-situ leaching uranium,and the feasibility of the horizontal well temporary plugging technology in optimizing the leaching efficiency was investigated. The results show that the plane distribution of the flow rate of the leaching solution in the " horizontal well injection-vertical well pumping" well pattern shows obvious inhomogeneity. The high flow contribution area of the leaching solution is mainly distributed near the area with the shortest horizontal distance between the horizontal well and the vertical well,while the flow contribution rate in the middle area between the adjacent vertical wells is low. The non-uniformity of the leaching solution flow decreases with the increase of the distance between the pumping vertical well and the horizontal well,and increases with the increase of the distance between the pumping vertical wells,and even there will be a zero contribution rate area,resulting in a leaching dead angle. However,changing the amount of pumping fluid has little effect on its distribution. In order to improve the problem of uneven flow distribution of leaching solution in well network,horizontal well plugging technology can be used in the later stage of in-situ leaching of uranium. By plugging the injection holes in the high flow area,more leaching solution can be guided into the low flow area,so as to effectively improve the overall leaching efficiency of uranium deposits.