Chondroitinase is a class of enzymes capable of degrading chondroitin sulfate into small polysaccharides, and has wide applications in medicine, biochemical engineering, food, and other fields. This chapter provides a detailed review of the research progress of chondroitinase, including its source and classification, enzyme activity assay, biochemical characteristics, degradation mode, structure, mechanism of action, preparation, modification strategies, and the application of chondroitinase. This section aims to help researchers fully understand chondroitinase and promote its application in research and production.