A battery state detection device detects a battery state and includes: a first permissible current calculating unit configured to calculate a first permissible current of a battery based on a voltage of the battery detected by a voltage detecting unit; a second permissible current calculating unit configured to calculate a second permissible current of the battery without using the voltage of the battery; and a permissible current determining unit configured to determine a permissible current of the battery corresponding to the battery state on the basis of at least one of the first permissible current and the second permissible current.