The utility model discloses a device for clearing nickel carbonyl in CO gas. The device successively comprises a reaction cylinder and an inverted-cone-shaped precipitator from top to bottom, wherein the reaction cylinder is fixedly connected with the inverted-cone-shaped bottom surface of the precipitator, and the reaction cylinder and the precipitator are communicated, an air inlet is formed in the upper part of the reaction cylinder, and a plurality of electric heaters are arranged at the bottom of the reaction cylinder, a powder outlet is formed at the bottom of the precipitator, an air outlet is arranged at the inverted-cone-shaped bottom surface, a vertical clapboard which is arranged near the air outlet is welded at the at the inverted-cone-shaped bottom surface in the precipitator. By adopting the device for clearing nickel carbonyl in CO gas provided by the utility model, the nickel carbonyl in CO gas can be cleared away in the process of extracting nickel through a carbonyl process, the CO gas can be repeatedly used, nickel powder is recycled, and resources are saved.