The device (100) according to the invention is used to clean medical instruments (60) having at least one instrument cavity (62) and at least two openings (63, 66), wherein the device (100) has a first fastening module (5) for detachably fastening the medical instrument (60) and a second fastening module (6) for detachably fastening a first container (7) for receiving liquid (insert in drawing) and/or air (insert in drawing), wherein the device (100) comprises a cleaning device cavity (25, 13, 16) which is designed such that when the medical instrument (60) and container (7) are fastened, the liquid and/or air can be flushed from the interior of the container (7) through the cleaning device cavity (25, 13, 16) into the instrument cavity (62). According to the invention, the device (100) has a first and a second operating position, wherein, in the first operating position, the liquid (80) can be flushed out of the container (7) through the cleaning device cavity (25, 13, 16) into the instrument cavity (62) and, in the second operating position, air can be flushed out of the environment through the container (7) and the cleaning device cavity (25, 13, 16) into the instrument cavity (62).
