A plurality of slots with different widths are provided in a plurality of line on a stationary blade surface. More specifically, the steam turbine stationary blade has a hollow nozzle with a penetrating space, which is connected with a diaphragm outer ring or inner ring, and a plurality of suction slots extending radially which are arranged on the blade surface. At a position where a water film deposited to the blade surface is thick, the width of a slot is smaller and at a position where the water film is thin, the width of a slot is larger.