Information storage device, information processing system, and setting method of data transfer mode of information processing device

An information storage device includes a storage that stores transfer data from an information processing device, the information storage device being removably connected to the information processing device, a switch unit that switches a data transfer mode of the information processing device in accordance with manipulation by a user, and a controller that controls the information processing device to transfer data in a mode in which data temporarily stored in a data storing area is transferred to the storage or in a mode in which data is transferred to the storage without being temporarily stored in the data storing area in accordance with the selection of the data transfer mode by the switch unit.