Extraction method of shark chondroitine

The invention provides an extraction method of shark chondroitine, belonging to the field of novel biology engineering technology; the extraction method solves the problems that the existing chondroitine has multiple extraction steps, complex process flows, low product yield, high protein and nitrogen impurity content; the extraction method of shark chondroitine comprises the following steps: A: alkali extraction; B. enzymolysis; C. ultrafiltration; D. oxidization and crystallization. The extraction method of shark chondroitine has simple process flow, less process steps and easy operation and can realize large-scale industrial production, the product yield can reach 17-22 percent and the purity can reach 90-96 percent.