Electronic key registration system

An electronic key registration system includes an electronic key (2) and a communication master (14). The electronic key (2) transmits at least one registration code. The communication master (14) receives the at least one registration code from the electronic key (2), obtains key information using the at lest registration code, and registers the obtained key information. The at least one registration code is set in accordance with the communication master (14) as a registration site of the electronic key (2). The communication master (14) includes a level determination unit (17) which determines a key registration security level when the electronic key (2) is registered to the communication master (14), and a registration execution unit (22) which obtains the key information using the at least one registration code based on the determined key registration security level and registers the obtained key information to the communication master (4). 种电子钥匙登录系统，包含：电子钥匙(2)，其发送至少1个登录代码；以及通信主机(14)，其从所述电子钥匙(2)接收所述至少1个登