To provide a key control device for safely controlling a key itself by a fingerprint certifying module.

A body 2 of the key control device 1 is detachably fixed to an installing base 3 firmly fixed to a wall by a hinge 4 and a key hook 5. When certifying fingerprints by a sensor part 14 of the fingerprint certifying module 13 arranged inside a freely openable-closable small door 8, a lock of a large door 7 by a hook 17 is released, and a key housing board 19 is opened outside, and a used key 22 can be returned, and can be taken out of a storage hole 21 by releasing a lock of a key holder 23 of the key 22 permitted in use for a fingerprint certified person. A printer 16 sealed inside the body 2 prints and outputs a code for specifying the fingerprint certified person, date data and existence data on the whole keys before releasing the lock of the large door 7, and prints and outputs the date and the existence data on the whole keys when closing the large door 7.