Abstract: A digital door lock, a digital door lock control server, and a digital door lock system are proposed. The digital door lock according to an embodiment of the present invention includes a driving unit formed in a door to move a deadbolt by an electric signal; a detection unit detecting whether the door is opened or closed; and controller configured to allow power to be provided from an external constant power supply when the deadbolt is drawn out of a body and is in contact with a power board inside a bracket formed in a door frame, and allow power to be provided from an internal power supply in the form of a primary battery or a secondary battery when the deadbolt is drawn into the body and is away from the power board.