β-amyrin is catalyzed by β-amyrin synthase, which is one of the most commonly occurring triterpenes in nature and is defined as a typical pentacyclic triterpene having an oleanane skeleton. The gene encoding β-amyrin synthase has been isolated and characterized from different plant families including Asteraceae, a very good source of triterpenoid saponins. Chicory (Cichorium intybus L.) , one of the most important medicinal plants from this family, has many applications in food and non-food industry . In this study, a 700 bp cDNA encoding a β-amyrin synthase was cloned from chicory by reverse transcription-polymerase chain reaction using degenerate primer designed from the conserved sequences among the known OSCs.