Abstract: Process of extracting collagen from skin of Amiurus nebulosus and partial characteristics were investigated in this paper.The influences of material liquid ratio,temperature and time to extraction,associate with orthogonal design to optimize the optimum extracting process of collagen by alkali solvent. The optimum distribution of parameters for extracting were determined as follows: material liquid ratio 1 ∶ 10,1.6%( w / w)Ca( OH)2,temperature 70 ℃ and 9 hours,and the optimized distribution of parameters led to 79.67% of extraction efficiency.Collagen extracted from alkali solvent was identified as collagen type I polypeptide according to UV spectrum scan and high performance liquid chromatography( HPLC) figure.