An additive manufacturing apparatus includes a chamber, a material layer former, and a guide member. The material layer former includes a base on which a molding region is present, a recoater head that moves on the base in a horizontal direction while discharging material, and a blade that levels the material to form a material layer. The guide member includes a feed chute that is configured to enable the material to be flowed, a shaft that is provided to shut a lower end portion of the feed chute and has a through hole, and a rotary actuator that rotates the shaft. The discharge of the material is switched to an on- or off-state by rotating the shaft.