In this study, a new extraction method combining principal component analysis and gray gravity center is proposed. The algorithm is used to solve the problem that the efficiency and accuracy of linear structured light stripe center extraction affect the measurement results. First, the image is subjected to Gaussian convolution. The threshold segmentation method is initially applied to extract the effective light stripe information from the image. Then, the gradient distribution and amplitude of the light stripe image are estimated, and the point with zero amplitude is considered to be the initial point. Subsequently, the principal component analysis is used to get the normal direction of the point. Along the normal direction, the two points with the maximum amplitude on both sides of the initial point are taken as boundary points. Finally, the gray center of gravity method is used to find the center of the light stripe within the boundary for determining the next initial point. The center of the light stripe is extracted through iteration. The proposed method is verified based on its average processing time and root mean square error. Experimental results show that the average processing time of the proposed method is approximately 1.701 s. Furthermore, the extraction accuracy of the proposed method is less than 0.0500 pixel compared with the Steger method.