Abstact： Objective:o investigate the physicochemical characteristics of soluble chicken type Ⅱ collagen (SCC Ⅱ). Methods:The absorption peak and isoelectric point (pI) of SCC Ⅱ solution were detected by absorption spectroscopy. The amino acid composition of SCC Ⅱ was determined by HPLC. The specific viscosity of different conditions of SCC Ⅱ solution was measured with Ubbelohde viscometer. The relative molecular weight was determined by SDSPAGE. Both SCC Ⅱ and heatdenatured SCC Ⅱ（D-SCC Ⅱ）were treated with pepsin, trypsin, α-chymotrypsin and type Ⅱ collagenase in vitro respectively, and the enzymolysis products were analyzed by SDS-PAGE and western blotting. Results:SDSPAGE showed that the relative molecular weight of α monomer was 120 000 approximately. Western blotting showed that α monomer could react with the rabbit anti-SCC Ⅱ antibody, and the D-SCC Ⅱ was pyrolyzed to more than 10 fragments which was almost immunostained in western blot. The maximum absorption peak of SCC Ⅱ solution was at 230 nm and the pI was 6.25 approximately. Identification of the amino acid composition of SCC Ⅱ showed that the contents of glycine, proline, glutamic acid and alanine were abundant whereas the aromatic amino acids were fewer. The specific viscosity of the SCC Ⅱ solution increased in a concentrationdependent manner and decreased in a temperaturedependent manner at the range of 25 to 45 ℃. No obvious change of immunoblotting images in SDS-PAGE of SCC Ⅱ was shown following the treatment of pepsin and α-chymotrypsin, but 10 positive bands appeared after the treatment with trypsin. After the treatment of pepsin, α-chymotrypsin or trypsin, no positive band of D-SCC Ⅱ was observed in immunoblotting. type Ⅱ collagenase could rapidly hydrolyze SCC Ⅱ and D-SCC Ⅱ. Conclusions:SCC Ⅱ is a type of collagen with unique physicochemical characteristics and has certain resistance to digestive enzymes. The active fragments of SCC Ⅱ could be obtained by treatment of trypsin.