The present invention includes a housing which is composed of an outside case which is installed on the outside surface of a door and an inside case which is installed on the inside surface of the door and combined to the outside case; a key input unit which is installed at the outside case of the housing and is to input a password; a door opening/closing unit which opens or closes the door according to the control signal from a control unit; the control unit which controls the opening/closing by the door opening/closing unit by comparing the input password and the preset password; an open button unit which is installed at the inside case of the housing and automatically opens the door by being connected to the control unit; a manual opening button unit which applies a certain signal to deactivate the auto-locking of the door when the door is closed; and a power supply unit which supplies driving power to each component. The door opening/closing unit opens the door by pushing or pulling a handle depending on the opening direction of the door. The opening of the door is detected through the speed change of a roller installed inside when the handle is pushed or pulled. Selective control to activate or deactivate the auto-locking of the door when the door is closed is available.
