The invention discloses a method for preparing iron ore concentrate for ironmaking from tin-containing iron ore. The method comprises the following steps: mixing the tin-containing iron ore and a sodium carbonate additive according to a certain ratio, agglomerating, drying, and performing reducing roasting under proper temperature and reducing roasting atmosphere; and separating magnetite concentrate by combining an ore grinding-magnetic separating method, and filtering and separating sodium stannate solution and filter residues from remaining nonmagnetic matters. The method is simple in process flow, mild in process conditions, low in cost and environmental friendly, particularly effective separation between tin and iron in the tin-containing iron ore is realized, the iron recovery rate is high, the content of tin in the obtained iron ore concentrate is low, and the iron ore concentrate can serve as a raw material during blast furnace ironmaking.