Qianzhou dry-salted duck is a traditional cure meat product.To investigate the degradation law of the proteins of the duck during processing,we used SDS-PAGE to analyze the degradation of the duck breast at different processing phases.The change of muscle fiber was investigated by scanning electronic microscopy.The results showed degradation was very obvious in whole muscle proteins,sarcoplasmic proteins and myofibrillar protein on day 14.During the period of 21 th day of curing to 14 th day of air-drying,the degradation of proteins was not obvious.Tight muscle fibers could be observed at 14 th day of curing.But it became loose with the muscle fibers reducing and fractured after the 7th day of air-drying.When the duck was air-dried for 14 days,the interspace among the muscle fibers were getting bigger,so the amount of muscle fibers reduces.The investigation provides scientific guidance of modification to the process of traditional Qianzhou dry-salted duck production.