A tubular-type deadbolt door lock with backset adjustment is disclosed.
To this end, the present disclosure is characterized by including: a deadbolt guide case having a predetermined length and including a deadbolt guide and a deadbolt lever therein that is coupled to be able to rotate with respect to the deadbolt guide; a deadbolt case installed at a front portion in the deadbolt guide case and having a predetermined space therein; a tubular deadbolt case coupled to surround an outer circumferential surface of a front portion of the deadbolt case; a worm gear positioned in the deadbolt case; a helical gear engaged under the worm gear and rotating with rotation of the worm gear; and a rack gear engaged with the helical gear, being able to move forward and backward with rotation of the helical gear, and connected the deadbolt guide, in which when the rack gear is moved in a front-rear direction, the deadbolt guide is also moved in the front-rear direction, so the deadbolt guide case is moved in the front-rear direction and a backset length is adjusted.