CO₂+O₂ in-situ leaching of uranium is an important mining method for sandstone-type uranium deposits in northern China.The methods of adding oxygen and measurement have always been the research objects of technicians.On the basis of analyzing the technical status and existing problems of oxygen mixing and metering in the field of CO₂+O₂ in-situ leaching of uranium, the advantages and disadvantages of oxygen addition and metering methods in domestic uranium mines are compared.By dissolving oxygen in a static mixer, the oxygen transfer rate and gas-liquid mixing efficiency are improved under the complex conditions of continuous changes of gas and hydraulic pressure; the gas mass flow controller is used for measurement to achieve the purpose of real-time adjustment and display of the oxygen addition amount.The error is controlled within 2%, which reduces the work intensity of employees; at the same time, the gas mass flow controller can be controlled by an automated program in the future to realize remote control of the concentration and metering of oxygen added, provide lean control mode for in-situ leaching production enterprises of sandstone type uranium deposit mining.