Chitin is the second most abundant biopolymer widely distributed in the marine and terrestrial environments. It is an insoluble linear polymer of beta-1,4-linked N-acetylglucosamine (GlcNAc). Chitin is abundantly present in the cell wall of fungi, exoskeleton of insects and crustacean cells. In nature, chitin exists as alpha, beta, and gamma crystalline forms. Degradation of chitin can be done using four enzyme systems: endochitinase; N-acetylglucosaminase; polysaccharide monooxygenase, and exochitinase. Endophytes isolated from marine algae have very good potent of producing chitinase and also have a wide application in the medical field like anticancer activity antimicrobial activity and many other industries like food, agriculture etc. Chitinases are applicable in agriculture fields to control pathogens. This review focuses on the major application of chitinase enzymes from different plant and microbial sources. © RJPT All right reserved.