Abstract: Stevia ( Stevia rebaudiand Bertoni) contains various functional components, such as glucosides, flavonoids, chlorogenic acid and so on. Steviol glycosides are of important value in food and pharmaceutical industry as sweetener. Flavonoids and chlorogenic acid also have antioxidant, anti-inflammatory and antitumor activities, which implies Stevia has great potentials.In this paper, we summarized extraction, purification and separation process of the three kinds of compounds.