Disclosed is a security device for securing a deadbolt door lock having an interior face plate and a lever movable between a locked position and an unlocked position. The security device includes a base member configured to be secured to the interior face plate of the deadbolt lock, and a lock member pivotably secured to the base member so that the lock member pivots between an open position and a closed position. The lock member is configured to prevent movement of the lever from the locked position to the unlocked position when the lock member is in the closed position and to permit movement of the lever from the locked position to the unlocked position when the lock member is in the open position.