The Concealed Door Lock provides impregnable door security and neat exterior design by combining a numeric lock and a concealed doorknob. The electronic touchpad is the only exposed element when the door is locked and the concealed doorknob protrudes once the secret code has been entered or an access card has been swiped. When exiting the room, the user simply pushes the inside handle lightly. Thanks to its gapless structure and simple operation, the Concealed Door Lock provides both watertight security and simply operation at the same time.