The invention discloses a method for preparing superfine iron powder by low-temperature hydrocarbon duplex reduction. The method comprises the steps of 1, carrying out ball milling on iron ore concentrate powder with certain purity, carbon powder and a catalyst; 2, uniformly mixing the materials subjected to ball milling in the step 1 according to a certain ratio; 3, placing the uniformly mixed materials in a protective atmosphere for heating reduction, and cooling to obtain primary reduced iron; 4, carrying out ball milling on the primary reduced iron in the step 3; 5, carrying out final reduction on the primary reduced iron subjected to ball milling in the step 4 in a hydrogen atmosphere, cooling the final reduced iron, then discharging the cooled iron out of a furnace to obtain reducediron powder; and 6, carrying out ball milling on the reduced iron powder obtained in the step 5 to obtain the superfine iron powder. Compared with the prior art, the method has the advantages of low reaction temperature, low energy consumption, low hydrogen consumption and the like, the high-quality superfine iron powder is easily obtained, the preparation process is simple, the energy consumptionis low, and the production cost is low.