A clean work device (10; 110) serving as culturing facility used to sequentially conduct culture work on different cells, comprising: a clean area including a work area disposed in a conveyance path of the cells, the work area having an inlet and an outlet in the conveyance path, a downflow air curtain being provided at least at the inlet and the outlet, the downflow air curtain blowing out of an air outlet port and being sucked by an air suction port that faces the air outlet port; and a moving unit (25; 125) consisting of a conveyor having a belt (64, 164) and configured to repeatedly perform an operation that moves a placement surface (25S; 125S) on which the cells are placed from the inlet side of the work area into the work area and, thereafter, moves the placement surface from an outlet side of the work area to the outside of the work area and, subsequently, moves back the placement surface to the inlet side again; the clean work device (10; 110) being characterized in that the clean area extends upstream and downstream of the work area; a cleaning unit (40; 140) is provided which comprises a cleaning liquid processing chamber (42; 142) and an ultraviolet processing chamber (44; 144), wherein the cleaning unit (40; 140) is configured to clean the placement surface during a period of time from when the moving unit moves the placement surface to the outside of the work area until the moving unit moves back the placement surface to the inlet side of the work area whereby toxicity of the placement surface is cleared, the moving unit is configured to repeatedly perform an operation that moves the placement surface along an upper horizontal lane including the work area in a predetermined direction, turns over and leads the placement surface to a lower horizontal lane that faces the upper horizontal lane, moves the placement surface along the lower horizontal lane in a direction opposite to the predetermined direction, and turns over and leads the placement surface to the upper horizontal lane, and the cleaning device is disposed so as to be adjacent to the lower horizontal lane. a clean area including a work area disposed in a conveyance path of the cells, the work area having an inlet and an outlet in the conveyance path, a downflow air curtain being provided at least at the inlet and the outlet, the downflow air curtain blowing out of an air outlet port and being sucked by an air suction port that faces the air outlet port; and a moving unit (25; 125) consisting of a conveyor having a belt (64, 164) and configured to repeatedly perform an operation that moves a placement surface (25S; 125S) on which the cells are placed from the inlet side of the work area into the work area and, thereafter, moves the placement surface from an outlet side of the work area to the outside of the work area and, subsequently, moves back the placement surface to the inlet side again; the clean work device (10; 110) being characterized in that the clean area extends upstream and downstream of the work area; a cleaning unit (40; 140) is provided which comprises a cleaning liquid processing chamber (42; 142) and an ultraviolet processing chamber (44; 144), wherein the cleaning unit (40; 140) is configured to clean the placement surface during a period of time from when the moving unit moves the placement surface to the outside of the work area until the moving unit moves back the placement surface to the inlet side of the work area whereby toxicity of the placement surface is cleared, the moving unit is configured to repeatedly perform an operation that moves the placement surface along an upper horizontal lane including the work area in a predetermined direction, turns over and leads the placement surface to a lower horizontal lane that faces the upper horizontal lane, moves the placement surface along the lower horizontal lane in a direction opposite to the predetermined direction, and turns over and leads the placement surface to the upper horizontal lane, and the cleaning device is disposed so as to be adjacent to the lower horizontal lane.