A method of producing an FRP molded article, the method being suitable for producing a thick FRP molded article, includes: placing a reinforced fiber base material in a cavity of a forming mold, such that a direction in which fiber sheets are laminated together (a sheet lamination direction) is a horizontal direction; impregnating a resin into the reinforced fiber base material by injecting the resin into the cavity in an anti-gravitational direction from an injection port provided below the reinforced fiber base material placed in the cavity; applying pressure in the sheet lamination direction to the reinforced fiber base material impregnated with the resin; and curing the resin impregnated in the reinforced fiber base material.