A device (1) for producing a three-dimensional object (2) through layer-wise solidifying of build-up material (13) at positions (43) corresponding to a cross-section of the object (2) to be produced in a respective layer comprises a coating device (12-14) for applying a layer of the build-up material (13) on a working plane (10), a solidifying device (20) for the selective solidifying of the build-up material (13) in the applied layer and a gas suction nozzle (34) for extracting gas from the device (1) by suction. The gas suction device (34) is thereby movably arranged and the device (1) is designed to control or to regulate a movement and/or orientation of the gas suction nozzle (34) as a function of a number of reference positions (51, 53, 55a, 55b, 55c, 55d).