Abstract: This paper introduces the research and development of automatic forming machine for butterfly chain in jewelry based on real-time positioning system,and detailedly focuses on the design principle,components,operation method of the automatic forming machine for butterfly chain.Finally the machine is tested by putting into factory production line.This machine works on the principle of the real-time positioning.Under the control of the embedded system,it can coordinate the entire machine with the chain feeding,detecting,stamping etc.The whole equipment includes stamping institutions,mounting rack,detecting agency,position-fixing agency,chain collecting institutions,bench and control box.Stamping institution includes punch, electromagnetic clutch and stamping die. The electromagnetic clutch is installed on the punch as an auxiliary part. This institution is mainly used to provide instantaneous momentum, which drives the hammer to fast extrude the chain link to complete the forging process. The detecting agency consists of infrared detectors,which can accurately detect the position of the link in different directions, processing the chain completely at one time chains feeding, thus reducing material wear and avoiding destroying the processed chain. The position-fixing agency consists of feeding conduit, shock absorber, chain detecting port fixed guide hole and chain collecting port fixed guide hole. Location of these two fixed guide hole is adjustable in vertical position. The holes size is also adjustable to adapt to different dimensions of the chain, The chain collecting institutions are in-stalled on the chain collecting port vertical plate, including stepping motor, chain collecting wheel with a chain scraper. Processed chains are collected into the collecting hole at last.This paper also introduces the operating method of the automatic forming machine for butterfly chain processing, including only a few simple manual manipulation procedures,namely the loading for unprocessed chain in the beginning and align the pressing point, the starting of the machine This machine uses infrared detecting and software programming control technology to realize real-time coordinating each circuit module with the pre-determined logic function orderly. The machine itself can intelligently detect the chain position continuously according to the actual length of the chain link, Feeding amount precision is effectively maximized while the unprocessed chain is approaching to its pressing point and dimension errors caused by link length difference are reduced.After being assembled and tested, automatic forming machine for butterfly chain can locate precisely and yield whole butterfly chain. That repeating experiments and practical application in factory showed that the butterfly chain products could possess precise size, beautiful shape with low rejection rate, and it has reached the requirements for the large-scale standardized and automatic production in factory. This machine is easy to operate by workers and one can watch several running machines at the same time. With highly productive efficiency and good effects, the machine has successfully served in producing workshop in precious metal jewelry processing enterprises, and it is of profound practical application significance.