In this study, the acid-soluble collagen (ASC) and pepsin-soluble collagen (PSC) were extracted from scale of grass carp by the methods of acid and acid-pepsin. The partial biological properties of these collagens were researched and compared with pig skin collagen (PC). Experiment results indicate that the ASC, PSC and PC were type Ⅰcollagen and the triple helical structure in the three collagen samples. The thermal transition temperature of PC(41.6 ℃) was obviously higher than that of ASC(34.8 ℃) and PSC(35.2 ℃). The in vitro enzyme degradation properties of collagens were influenced by many factors, such as the enzyme variety, the isolation methods of collagen, the collagen sources, the thermal treatment and self-assembly degree of collagens. PSC can be degraded by collagenase, trypsin and papain, but the degradability of collagenase is the most notable. In the same conditions, the order of in vitro enzyme degradation ratio of these collagens were ASC>PSC>PC. The enzyme degradation ratio of these collagens could be increased after thermal treatment and could be decreased after self-assembly processing. The collagen sponges of ASC, PSC and PC have different structural and mechanical characterization. Sponges of ASC and PSC were porous and had low mechanical strength but the sponge of PC was the other way round.