The substrate treatment apparatus according to the present invention includes a substrate holding mechanism which holds a substrate, a nozzle body having a spout which spouts an etching liquid toward a major surface of the substrate held by the substrate holding mechanism, a nozzle body movement mechanism which moves the nozzle body in a predetermined movement direction so as to move an etching liquid application position at which the etching liquid is applied on the major surface, a first flexible sheet attached to the nozzle body to be brought into contact with a portion of the major surface located on one of opposite sides of the etching liquid application position with respect to the movement direction, and a second flexible sheet attached to the nozzle body to be brought into contact with a portion of the major surface located on the other side of the etching liquid application position with respect to the movement direction.