A substrate etching apparatus includes: a cassette to receive a substrate that has finished a previous process, and transfer the substrate; a first robot to take the substrate out of the cassette; a second robot to receive the substrate from the first robot and move the substrate mounted thereon vertically up and down; an etching cassette comprising a support to support the substrate and a holder to fix the substrate loaded from the second robot; a cassette fixing unit to fix at least one or more etching cassettes and being rotated at a pre-set angle to allow the substrate to be disposed perpendicular to the ground; and an etching unit to etch the substrate disposed perpendicular to the ground by the cassette fixing unit.