Natamycin is a fungicidal antimycotic of the polyene macrolide group, with characteristic of nature, broad spectrum, high efficiency and safefy. It can effectively inhibit the growth of yeast and mould and prohibit the emergence of aflatoxin which is a filamentous fungi. It has been widely used for food preservation and treatment and disease caused by fungi. It also can be used as active compound to produce eye drops, gynecological suppository and skin cream etc.