A quantum entity authentication apparatus and method. The quantum entity authentication apparatus includes a quantum state preparation unit for preparing an authentication quantum state that is generated based on an authentication key previously shared with an entity, a quantum channel verification unit for transmitting a quantum state, generated by performing an operation using a prestored unique operator on the authentication quantum state, to a quantum measurement device, and for verifying security of a quantum channel by using a result of Bell measurement and the authentication quantum state, the result of Bell measurement being revealed by the quantum measurement device for the quantum state, and a quantum entity authentication unit for, when the security of the quantum channel is verified, authenticating the entity using the result of the Bell measurement and the unique operator.