A structure for racking substrates includes first to fourth main legs isolated from one another at intervals wider than widths of both long sides and both short sides of a substrate, first to fourth protrusions respectively protruded from the first to fourth main legs in a direction of the long sides or the short sides of the substrate, a first side support bar coupled to the first and second protrusions and supporting an edge of one long side or one short side of the substrate, a second side support bar coupled to the third and fourth protrusions and supporting an edge of the other long side or the other short side of the substrate, at least one auxiliary leg disposed between the first and second main legs, or the second and third main legs, or the third and fourth main legs, or the fourth and first main legs, and at least two central support bars coupled to the auxiliary leg, extended parallel to the long sides or the short sides of the substrate, and supporting a central portion of the substrate.