PURPOSE: To easily refine uranium contg. molybdenum and to produce an yellow cake satisfying the specifications by bringing a uranium exudation liquid contg. molybdenum into contact with a chelating resin contg. a specified group.

CONSTITUTION: A uranium exudation liquid contg. molybdenum is brought into contact with a chelating resin contg. an amidoxime or dithiocarboxylic group as a functional group, hence molybdenum is selectively adsorbed on the resin, and a chelating resin-treated soln. almost free of molybdenum is obtained. The soln. is neutralized and previously to obtain an yellow cake. Since molybdenum is previously removed in this way, the liq.-liq. extraction to remove other impurities and the refining of uranium are facilitated.