To facilitate the change of a deposited cryptographic key in a star- shaped cipher communication system and to disable cipher communication without depositing the cryptographic key.

Master terminal equipment 3 generates a cryptographic key for cipher communication with slave terminal equipment 4 through a base station 2 and distributes it to the base station 2 and the slave terminal equipment 4. The cryptographic key is deposited from the master terminal equipment 3 to a deposit center 1. The deposit center 1 generates managing information from the cryptographic key and applies it to the base station 2. The base station 2 converts communication information to be repeated on the basis of the correspondent managing information. Since terminal equipment 3 and 4 are disabled in deciphering of received enciphered sentences without depositing the cryptographic keys, normal communication is disabled. When it is necessary to change the cryptographic key, the key can be freely changed and deposited online from the master terminal equipment 3.