PURPOSE: To facilitate the key management and the door opening/closing opera tion by providing a key part with an unlock information storage means and providing a lock part with a control circuit which reads unlock information and compares it with preliminarily stored unlock allowing information to discrim inate whether unlock is permitted,

CONSTITUTION: The lock part consisting of an infrared ray receiving part 8, a control circuit 9, an outer door automatic lock mechanism 3, and a paper money unit automatic lock mechanism 5 reads unlock information of an infrared key 6 or 7 and compares it with unlock allowing information stored in the lock part, and unlock is executed when unlock is permitted as the comparison result, but unlock is not executed when it is not permitted. In this case, unlock object range set data to determine the range of the unlock object is included in unlock information of the key part. Thus, keys are relatively easily managed, and the history of door opening and closing is easily managed, and a lock device is obtained where the door is easily opened and closed.