The invention relates to a palladium chloride-copper chloride/manganese-cerium catalyst. The catalyst is characterized in that active components include palladium chloride and copper chloride; a carrier is a manganese-cerium composite oxide. The palladium chloride and the copper chloride are loaded on the carrier by an immersion method and are baked at a high temperature to obtain the needed catalyst. The catalyst can be catalytically oxidize carbon monoxide under room-temperature, low-concentration and high-airspeed conditions and is applicable to eliminating the low-concentration carbon monoxide in semi-closed spaces including road tunnels or underground parking lots and the like. The catalyst is prepared by using the immersion method; the preparation method is simple; the use amount of noble metals is low and the cost is low.