A lawn mower contains: a work unit including a housing having a downward-facing opening and a cutter blade rotatably provided in the housing such that when rotated, the cutter blade cuts grass and generates a transport air flow flowing from the opening of the housing to inside; a grass clippings receptacle configured to receive grass clippings cut by the work unit; a grass clippings transport passage connecting an interior of the housing with the grass clippings receptacle; a shutter device including a shutter configured to selectively open and close the grass clippings transport passage and an actuator configured to drive the shutter; a controller configured to control the shutter device; and a pressure sensor provided in the grass clippings transport passage to detect a pressure in the grass clippings transport passage, wherein the controller is configured to control the shutter device in accordance with the pressure detected by the pressure sensor.