A case for storing a battery which supplies drive power for a headphone includes a case body to which the battery is stored and which is capable of being inserted to an insertion hole formed at a headphone chassis and a lock pawl which is capable of being locked with a lock hole formed at the headphone chassis, while a positive terminal which is connected to a positive electrode of the battery stored in the case body and a negative terminal which is connected to a negative electrode of the battery stored in the case body are arranged, and then, a leading terminal which is connected to either the positive electrode or the negative electrode is arranged at the case body and the leading terminal is connected to either the positive terminal or the negative terminal.