We investigated sericin extracted from sericinjam, which was inbred at National Academy of Agricultural Science, Suwon, Korea. Sericinjam sericin is composed of 5 fractions: 250 kDa, 120 kDa, 90 kDa, 70 kDa and 40 kDa. Amino acid analysis showed that the major amino acids of sericinjam sericin were Ser, Gly, Asp, Glu, Thr and Ala. Infrared spectra showed that sericinjam sericin has $eta$-sheet structure. Thermal property of sericin was investigated using DSC and then they showed characteristic degradation peak at around $215{sim}240^{circ}C$.