The shrinkages and physical properties of silk yarn were studied on the effect of treatment concentration, time and temperature with various neutral salts. The degummed silk yarn was shrunk about 35 percent by highly concentrated solution of Ca(NO3)2 on conditions of S.G.(special gravity) 1.45 at 9$0^{circ}C$ or S. G. 1.46 at 8$0^{circ}C$. About 40 percent of silk yarn was contracted in length by the treatment of CaCl2 solution on conditions of S. G. 1.33 at 9$0^{circ}C$ for 5 mins. or at 85$^{circ}C$ for 10 mins. By treating the concentrated solution of LiBr the silk yarn showed about 40 percent of shrinkage on a conditions of S. G. 1.38, $25^{circ}C$ 24hrs. The physical properties of salt-treated silk yarn could be significantly changed with shrinkage variations. There were some differences in shrinkages between different type of salts. However, it was observed that generally the tenacity was decreased and breaking elongation increased as the shrinkage increased. The bulkiness of salt-treated silk yarn was increased by 110 to 120 percent compared with untreated yarn.