1. A self-localization device, comprising: a movable carrier, for performing a movement and a rotation on a plane, wherein the movement and the rotation are independent; a laser image-taking device, disposed on the movable carrier, for acquiring an i-th lot point data in a space at a time point t i when the movable carrier moves, where i is an index number from 1 to n, and n is an integer; and a processor, controlling the laser image-taking device, and receiving coordinates of the i-th lot point data (iε[1,n]), wherein the processor executes a K-D tree algorithm to perform a comparison and merge process to a first and the i-th lots point data, so as to establish a two dimensional (2D) profile, and the K-D tree algorithm refers to that the i-th lot point data (iε[1,n]) obtained by the laser image-taking device is processed by the processor to generate a K-D tree structure, and a data comparison, a data merge or a carrier position update is performed between the K-D tree structure and the i-th lot point data obtained through a current scan.