The carbon-supported nitrogen purification device can remove impurities such as oxygen, water, carbon dioxide, dust and other impurities in the general nitrogen of air separation. The device first uses a hydrogen-free deoxidizer-palladium carbon fiber to directly remove oxygen in nitrogen. The oxygen removal capacity is large, and the gas production cost is low. The principle is that the trace oxygen in the nitrogen reacts with the carbon in the deoxidizer to generate a trace amount of carbon dioxide, and the generated trace amount of carbon dioxide and the trace amount of water in the system are adsorbed by the desiccant, and then heated and regenerated after the adsorption is saturated. The two drying towers are used alternately, so that the whole system can work continuously. The nitrogen purification device adopts a medium-pressure purification process, which has the advantages of compact structure, simple operation, good purification effect and low energy consumption. The deoxidizer is designed to be replaced every two to three months, and the desiccant is circulated and regenerated in the device. The purification device is equipped with electrical control and instrument box, which can realize automatic control.