The invention relates to the technical field of a novel automatic sorting structure for a projection-weld square nut. Specifically, a through slot for accommodating the projection-weld square nut is formed in the end surface of a fan-shaped plate; a sorting stop pin, an induction switch and a gas blowing hole are separately formed in the end surface and the bottom surface of the through slot; thefan-shaped plate is improved, so that the projection-weld nut which enters the through slot drops to the stop pin through self-gravity, and is matched with the induction switch and a gas source, a concave surface of a welded nut welding point bump is utilized for circulating and screening, and the screened and sorted welded nut welding point bump is consistent in direction, and therefore, the automatic sorting purpose is achieved. A fastening part is automatically connected for being the technology trend for existing car and household application. The novel automatic sorting structure solves the structural problem of automatically sorting projection-weld nuts, so that the nuts can be automatically projection-weld. According to the main technical scheme and the technical key point, the structure is matched with a detecting system, so that an integrated structure for projection-weld nut detecting, signaling, conveying and sorting is completed.