Triterpenoids (such as glycyrrhetinic acid

saponin ) is the main existence form of many drugs that play a pharmacological activities within the cells. Except used as the main active ingredients of drugs

some of them also can be used as a sweetener. But the amount of triterpenoids in plant (the origin source) is very low

which restrict its development and utilization. With the discovery of key enzymes in terpenoids metabolism

the whole metabolic pathway of terpenoids is clear increasingly. In recent years

the rapid development of synthetic biology lays a solid foundation for triterpenoids production by microbial fermentation. This paper reviews the triterpenoids biosynthesis pathway in Saccharomyces cerevisiae and cytochrome P450 monooxygenase (CYP450) which plays an important role in the whole pathway.