In order to realize the efficient extraction of collagen from fish scales, acid-enzyme coupling methods was used for collagen extraction based on the optimized decalcification, mixed-acid and enzymatic extraction. The optimum decalcification of fish scales was as follows. The solid to liquid ratio was 8100, soluted in 1.0 mol/L hydrochloric acid, and then reaction at 20 ℃ for 1.0 h. The best conditions for collagen extraction using mixed acid were 112 of acetic acid, 110 of citric acid, and 112 of lactic acid for 3 d extraction and the extraction yield of it was 48.14%. The best enzymatic extraction conditions were shown to be 450 U/g of pepsin at the extraction temperature of 30 ℃ for 72 h and the yield was 45.26%. Acid-enzyme coupling method showed better effect than acid or enzymatic extraction only, even though repeating them twice respectively was not as effective as the coupled one, in spite of relatively high cost and time-consuming (P<0.05). We could obtain 84.61% of the collagen using mixed acid followed by enzymatic extraction , and the extracted collagen was identified to be type I one using SDS-PAGE.