Liver diseases are one of the leading causes of death in the world. In spite of tremendous advances in modern drug research, effective and safe hepatoprotective agents are still in urgent demand. Natural products are undoubtedly valuable sources for drug leads. A number of natural triterpenoids were reported to possess pronounced hepatoprotective effects, and triterpenoids have become one of the most important classes of natural products for hepatoprotective agents. However, the significance of natural triterpenoids has been underestimated in the hepatoprotective drug discovery, with only very limited triterpenoids being covered in the reviews of hepatoprotective natural products. In this paper, ca 350 natural triterpenoids with reported hepatoprotective effects in ca 120 references between 1975 and 2016 will be reviewed, and the structure-activity relationships of certain types of natural triterpenoids, if available, will be discussed. Patents are not included.