The utility model discloses an argon purification unit, which comprises a CO2 filter. A hydrogen-free deoxygenation unit is connected in series in an output pipeline of the CO2 filter, and comprises two adsorption column devices which can be connected in series or parallel; the adsorption column devices comprise casings; YBCO molecular sieves are arranged in the casings; heating devices are also arranged on the adsorption column devices; and an output pipeline of the hydrogen-free deoxygenation unit is connected on a bottling mechanism of a compressor. The hydrogen-free deoxygenation unit utilizes the oxygen respiration property of YBCO, and has simple process procedure, requires less equipment and is convenient to operate. More importantly, no matter in purification process or in the regeneration process after the purification, the YBCO molecular sieves can deoxidize or regenerate without being added with hydrogen, so that no post-processing dewater and dehydrogenation device needs tobe mounted, the control is simple and has little possibility of being affected by external factors; and with the YBCO catalyticaction, the product purity is extremely high.