(Problems) Providing a method and an apparatus for producing a solid fuel, capable of suppressing increase in dust coal concentration in circulating oil.(Solving Means) The method for producing a solid fuel comprises a mixing step of mixing porous coal with a mixed oil containing a heavy oil and a solvent oil to prepare a raw material slurry; an evaporation step of heating the raw material slurry to promote dehydration of the porous coal while impregnating the mixed oil into pores of the porous coal to obtain a dehydrated slurry; a solid-liquid separation step of separating a resulting upgraded porous coal and the mixed oil from the dehydrated slurry; a final drying step of drying the separated upgraded porous coal with a carrier gas, and subsequently condensing a vaporized mixed oil in the carrier gas by cooling, while capturing the porous coal in the carrier gas by atomization of the condensed mixed oil, thereby recovering the mixed oil; and a circulation step of returning the mixed oil separated and recovered in the solid-liquid separation step to the mixing step, and the method is characterized by further comprising a supply step A of supplying the mixed oil recovered in the final drying step to the solid-liquid separation step. The apparatus for producing a solid fuel adopts the method.