Aiming at the defect that the traditional gray gravity method cannot accurately extract the center line of the region with large curvature change in the line structured light strip, an algorithm for extracting the center line of line structured light based on improved gray barycenter method is proposed. The region of interest is extracted based on the threshold method, and the noise points in images are filtered through the open and close operation to obtain the image to be processed with relatively high quality. Center points of the light strip through the gray gravity method. And a rectangular calculation area is set up. The direction vector and normal vector of the initial points are extracted according to the least square method. Finally, the offset of the initial point in the normal direction is recalculated in the rectangular area to obtain the exact coordinates of the center point. Experimental results show that the proposed algorithm can accurately extract the center line from the region with large curvature change in the center of line structured light,achieving a mean precision of 0. 096 pixels, a mean precision rate of 44. 2%, and an average extraction speed of 0.082 seconds.