In a stocker entry task control method employed in a semiconductor wafer cassette transportation apparatus that has high transportation ability of a semiconductor wafer cassette, a host computer sends an interrogation to a stocker in which a semiconductor wafer cassette is to be stored whether there is an available storage site therein. The stocker ascertains the storage site if available. Then, the host computer sends a transportation task instruction to an inter-stocker transport device or an automatic carrier. Alternatively, an entry task instruction is sent to the stocker.