A robot hand having a suction holding unit on one face side holds a plate-shaped work by suction. An outer circumferential edge of the plate-shaped work is held, without contact with a surface of the plate-shaped work, by an outer circumference holding unit provided on the other face side. The robot hand can be used to hold the plate-shaped work yet to be worked by the suction holding unit, and to hold the plate-shaped work having been worked by the outer circumference holding unit. This prevents working debris from being deposited on the plate-shaped work yet to be worked and prevents defective working from occurring. In addition, since the plate-shaped work having been worked is held by the outer circumference holding unit, the robot hand does not make contact with surfaces of the worked plate-shaped work, and, accordingly, no contact marks are formed on the surfaces of the work.