β-Amyrin is a pentacyclic triterpenoid that is oleanane substituted at the 3beta-position by a hydroxy group and containing a double bond between positions 12 and 13. It is one of the most commonly occurring triterpenoids in higher plants. It has a role as a plant metabolite and an Aspergillus metabolite. It is a pentacyclic triterpenoid and a secondary alcohol. It derives from a hydride of an oleanane.