A pairing authentication method includes the steps of installing application software on first and second electronic devices to create first and second public keys thereon, respectively; connecting the first electronic device to a closed storage device for the former to generate a checking key; storing the first public and the checking key on a security chip of the closed storage device; connecting the second electronic device to the closed storage device for the former to generate an authorization key that matches the checking key, and transmitting the second public and the authorization key to the closed storage device; and the closed storage device verifying the authorization key matches the checking key and storing the second public key on the security chip. Therefore, only a cardholder knowing the checking key can use the closed storage device and no risk of asset theft exists if the closed storage device was lost.