The present invention relates to a cold wallet apparatus. The cold wallet apparatus includes a homomorphic encryption generation module configured to generate homomorphic encryption using personally identifiable sensitive information; a first authentication code extraction module configured to extract an authentication code from the homomorphic encryption; a second authentication code extraction module configured to extract an authentication code from physical unclonable function (PUF) information of the cold wallet apparatus; a private key generation module configured to combine the authentication code extracted from the homomorphic encryption and the authentication code extracted from the PUF information to generate a private key; and a transaction signature module configured to perform a transaction signature using a wallet account and a wallet address generated based on the private key.