Handler for testing semiconductor devices

A handler for testing semiconductor devices is disclosed which is capable of simplifying the process carried out in an exchanging station, namely, the process of loading/unloading semiconductor devices in/from test trays, and greatly increasing the number of simultaneously testable semiconductor devices. The handler includes a loading station, an unloading station, test trays, an exchanging station comprising a horizontal moving unit for horizontally moving a selected one of the test trays by a predetermined pitch at a working place, a test station in which at least one test board having a plurality of test sockets to be electrically connected with semiconductor devices is mounted, the test station performing a test while connecting the semiconductor devices in one of the test trays, which is fed from the exchanging station to the test station, to the test sockets, device transfer units for transfer the semiconductor devices between the loading station and the exchanging station and between the exchanging station and the unloading station, respectively, and a tray transfer unit for transfer the test trays between the exchanging station and the test station.