The traditional evaporation process has obvious disadvantages when treating uranyl nitrate with a uranium concentration less than 10 g/L, such as more ancillary equipment, high energy consumption, and high cost. By contrast, nanofiltration equipment has low integration, and multivalent cations can be rejected effectively by nanofiltration membranes. In this work, a spiral-wound DK1812 nanofiltration membrane with an area of 0.325 m2 was used to treat a uranium nitrate solution with a uranium concentration of 10 g/L. The uranium concentration in the permeate is 16.91 mg/L, which means that the uranium rejection rate is 99.83% and the permeate flux of the solution is 71.1 L/(m2·h) under the conditions of a feed temperature of 30°C, a tangential velocity of 30 cm/s, and a transmembrane pressure of 1.5 MPa.