A storage device is configured to be connected to a host device via a physical cable which includes a power line and a data line. The storage device includes a non-volatile memory, a data path controller configured to temporarily deactivate the data line while power is supplied from the host device via the power line, and a memory controller. The memory controller includes a biometric module configured to receive biometric data and perform user authentication based on the biometric data; a biometric processing circuit configured to change a state of the memory controller, based on a result of the user authentication; and a data processing circuit configured to encrypt and decrypt data. The data path controller is configured to temporarily deactivate the data line in response to the changed state of the memory controller.