A stack forming apparatus includes a nozzle device that includes a nozzle configured to supply powder to a target and to irradiate the target with an energy beam, and a supply device which selectively supplies the nozzle with a powdery forming material to form layers that form a formation, and a powdery support material to form a support layer which permits the layers formed by the forming material to be formed on the top surface thereof. The stack forming apparatus further includes an optical system which outputs the energy beam to the nozzle, and a controller which drives the nozzle and which is configured to control the supply amount of the forming material to be supplied to the nozzle and the supply amount of the support material and which stacks the layers formed by the forming material and the support layer on the target.