A method of vacuum-assisted RTM includes disposing a resin distribution medium on one surface of a reinforcing-fiber substrate, covering the whole with a bag material, reducing the pressure inside the bag material, and injecting a resin into the resin distribution medium to distribute the resin substantially in in-plane directions and then impregnate the resin into the reinforcing-fiber substrate in the thickness direction. The method is characterized in that the flow resistance of the resin distribution medium itself during resin distribution is changed in in-plane directions of the reinforcing-fiber substrate, in accordance with a difference in fiber weight per unit area or density between parts to be impregnated with resin of the reinforcing-fiber substrate present in a plane direction of the reinforcing-fiber substrate, or in accordance with a difference in distance from a resin impregnation initiation part to a resin impregnation completion part between parts to be impregnated with resin of the reinforcing-fiber substrate present in a plane direction of the reinforcing-fiber substrate.