Abstract: Objective The aim is to tackle problem of extraction process of typical weld feature points, such as fillet joint, lap joint and V-groove is complex. Methods A geometric feature analysis method based on line fitting is proposed. Image preprocessing and stripe center line extraction is achieved by using the characteristics of laser stripe of linear structured light in the image. First of all, the extracted stripe center point sets n are sorted according to coordinates from small to large. On these weld features, the key point n₀ is determined by formula of point-to-line distance, so that the center point sets are divided, and divided point sets are respectively fitted by lines, finally the feature points are obtained through the intersection point of two lines. Results The results show that the method has simple process and effective in detecting information of feature points on the welds. The max ordinate error is about 0.273 mm, which meets the requirements of weld detection test. Conclusion The method can quickly and exactly divide point sets to which the feature line belongs to, and detect feature points of various welds, such as fillet joint, lap joint and V-groove. The method has good adaptability.