A security-enhanced cloud system is provided. The system includes a mobile terminal for creating fingerprint recognition information and face recognition information or biometric recognition information by recognizing a fingerprint and a face or a body of a user; and a private virtualized cloud server allowing use of first class document data of a high security level and second class document data of a low security level by permitting only connection of a computer of the user after being activated in response to the wake-on command transmitted from the control system. The user authentication is completed by transmitting the created fingerprint recognition information and face recognition information or biometric recognition information to the control system in response to the authentication request.