Flash memory device capable of reusing defective flash memories

A flash memory device capable of reusing a defective flash memory is provided to increase productivity of the flash memory without costs for disposal of defective flash memory by reusing a normal flash memory. A flash memory(120) includes a first individual flash and a second individual flash. A controller(160) controls the operation of the flash memory. A conversion unit(150) is connected between the flash memory and the controller, and controls the operation of the first individual flash and the second individual flash selectively. The conversion unit controls the path of a state signal(#R/B1) and a chip selection signal(#CE1) supplied to the first individual flash from the controller, and controls the path of a state signal(#R/B2) and a chip selection signal(#CE2) supplied to the second individual flash from the controller.