A substrate position alignment device includes a plurality of rotary tables which hold a plurality of substrates to be vertically spaced apart from each other, a rotation drive device which synchronously rotates the plurality of rotary tables, a plurality of support elements which support the substrate on the rotary table, support element drive members which independently and horizontally move the plurality of support elements between inward positions and outward positions, and up-down devices which move up and down the plurality of support element drive members. The substrate position alignment device operates the rotation drive device, the support element drive members and the up-down device based on the positions of notches of the substrate, to align the notches of the plurality of substrates with a reference rotational angle position.