Abstract: Collagen gels were prepared through the cross-linking with microbial transglutaminase (MTG). The effect of different concentrations of microbial transglutaminase on the structure and properties of collagen gels were studied, mainly concentrating on the appearance, FI -IR, thermal stability, enzymatic resistance, gel strength and water absorption of the gels. The results of thermal stability, enzymatic resistance, gel strength and water absorption of the gels showed that the optimum condition for cross-linking of collagen gel was 0.04 U/mL MTG. There was no obviously changed in the appearence of collagen gels, the FI-IR showed that the triple helix structure of collagen was maintained integrity. At the optimum concentration of MTG, the residual weight of thermogravimetric, the enzymatic resistance degradation ratio in vitro, the gel strength and the water absorption ratio increased by 11.79%, 10.21%, 324 g and 1.65 *10³ % compared with those of uncross -linked collagen gel, respectively. However, the thermal denaturation temperature slightly increased.