The invention discloses a private key safety management method based on an identity public key cryptography system. The private key safety management method comprises the steps of: system parameter establishment; private key generation algorithm; private key recovery algorithm; signature algorithm; and authentication algorithm. Through the combination of password blinding and private key slicing, in the process of distribution, storage, backup and recovery, the private key is sliced, and part of the private key is subjected to password blinding in the backup process, even in the use process, the authentic private key of a user is not needed to be calculated, and the private key is used in a slicing manner, so that the safety of the private key is ensured. Compared with the prior art, the private key is subjected to password blinding only in the backup process, the safety of the private key can be ensured without any safety measure in the distribution, storage and use processes, on one hand, the escrow problem of the private key is solved, on the other hand, the backup and the recovery of the private key can be realized easily, and for users, the private key safety management method is convenient in use and low in cost.