In-situ uranium leaching and mining treatment method by adding O2 into CO2

The invention provides an in-situ uranium leaching and mining treatment method by adding O2 into CO2. The invention comprises the steps of (1) adding O2 into leaching solution, then injecting an underground mine-water contained layer into a liquid injection pipeline, and preparing the leaching solution by adopting different oxygenation concentrations according to different underground leaching periods; (2) adding 100-300mg/L of CO2 into the leaching solution containing uranium; (3) conducting ion exchange adsorption on the leaching solution containing uranium, adopting macroporous styrene strong-base anion exchange resin, adsorbing to obtain saturated resin adsorption tail solution; and (4) washing saturated resin by adopting an eluting agent, and then analyzing uranyl carbonate ion solution to obtain Na2U2O7 sediment slurry and sediment mother liquor. According to the method, a high-temperature heating device is eliminated, so that the energy consumption and equipment investment are lowered greatly, the alkali consumption is lowered, control parameters are refined, the consumption of alkali is saved, and the production cost is lowered.