Abstract: A columnar laminar flow generation device includes: a placement part on which to place a processing target; a gas blow-out part having an opening; and a gas suction path; wherein the placement part is positioned in a space whose outer periphery surface is constituted by extending the interior wall of the opening in the direction vertical to the opening; the opening has, in its interior wall, a gas blow-out port through which a gas is blown out in one direction vertical to the opening; and the gas suction path is formed in such a way that it suctions the gas in the direction opposite to the one in which the gas is blown out. The columnar laminar generation device is capable of generating columnar laminar flows.