A lithographic device with a lithographic irradiation system (1, 13) which is fastened near a lower side to a mounting member (5) of a frame (7). The device is provided with a unit (65) which is formed by a positioning device (37), with which an object table (21) arranged below the irradiation system (1,13) is displaceable, and by a support member (35), over which the object table (21) is guided by means of an aerostatic foot (31). In an operational position, the unit (65) is coupled to a carrier (67) by means of coupling members (73), the carrier (67) being suspended from the mounting member (5) by means of suspension elements (79, 81, 83), so that the unit (65) is arranged between lower frame supports (25) of the frame (7) and a compact construction is obtained.; The unit (65) can be rotated from the operational position to an end position, in which the unit (65) is entirely outside the frame (7) and is easily accessible for maintainance, by means of a rotation mechanism (87) and a swivel mechanism (89). The lithographic device can be used inter alia for irradiating semiconductor substrates, a semiconductor pattern provided on a mask (11) being imaged on a semiconductor substrate (19) provided on the object table (21) by means of the irradiation system (1, 13).