A method of manufacturing molten iron, comprising the steps of: reducing fine iron ores into reduced fine iron by using a multi-stage fluidized furnace; manufacturing high-temperature compacted iron by compressing the reduced fine iron using a compacted iron manufacturing device; crushing the high-temperature compacted iron by using a crushing device; conveying the crushed compacted iron to a charging device; conveying some of the crushed compacted iron to a compacted iron storage tank; distributing the crushed compacted iron to the charging device or the compacted iron storage tank by using 2-direction chutes; and charging the compacted iron from the charging device into a smelting furnace and melting the charged compacted iron by combusting fine or lump coal, wherein if the high-temperature compacted iron necessary for the smelting furnace is able to be manufactured through the multi-stage fluidized furnace, the compacted iron manufacturing device, and the crushing device, excess high-temperature compacted iron exceeding an amount of the high-temperature compacted iron necessary for the smelting furnace is manufactured, and the excess high-temperature compacted iron is intermittently conveyed to and stored in the compacted iron storage tank by way of an action of the 2-direction chutes, wherein if the high-temperature compacted iron necessary for the smelting furnace is unable to be manufactured through the multi-stage fluidized furnace, the compacted iron manufacturing device, and the crushing device, the compacted iron stored in the compacted iron storage tank is continuously supplied to the smelting furnace via a conveyance device (450, 400), wherein if a ratio of a yield of high-temperature compacted iron manufactured by the multi-stage fluidized furnace the compacted iron manufacturing device, and the crushing device and demand quantity of high-temperature compacted iron necessary for the smelting furnace is defined by an excess rate as below, the excess rate = (yield of the high-temperature compacted iron)/ (demand quantity of the high-temperature compacted iron) x 100, the excess rate is 110% to 120%. reducing fine iron ores into reduced fine iron by using a multi-stage fluidized furnace; manufacturing high-temperature compacted iron by compressing the reduced fine iron using a compacted iron manufacturing device; crushing the high-temperature compacted iron by using a crushing device; conveying the crushed compacted iron to a charging device; conveying some of the crushed compacted iron to a compacted iron storage tank; distributing the crushed compacted iron to the charging device or the compacted iron storage tank by using 2-direction chutes; and charging the compacted iron from the charging device into a smelting furnace and melting the charged compacted iron by combusting fine or lump coal, wherein if the high-temperature compacted iron necessary for the smelting furnace is able to be manufactured through the multi-stage fluidized furnace, the compacted iron manufacturing device, and the crushing device, excess high-temperature compacted iron exceeding an amount of the high-temperature compacted iron necessary for the smelting furnace is manufactured, and the excess high-temperature compacted iron is intermittently conveyed to and stored in the compacted iron storage tank by way of an action of the 2-direction chutes, wherein if the high-temperature compacted iron necessary for the smelting furnace is unable to be manufactured through the multi-stage fluidized furnace, the compacted iron manufacturing device, and the crushing device, the compacted iron stored in the compacted iron storage tank is continuously supplied to the smelting furnace via a conveyance device (450, 400), wherein if a ratio of a yield of high-temperature compacted iron manufactured by the multi-stage fluidized furnace the compacted iron manufacturing device, and the crushing device and demand quantity of high-temperature compacted iron necessary for the smelting furnace is defined by an excess rate as below, the excess rate = (yield of the high-temperature compacted iron)/ (demand quantity of the high-temperature compacted iron) x 100, the excess rate is 110% to 120%.