Abstract:Urushiol is a unique biochemical component in Anacardiaceae, which has excellent biological activities in antioxidation, antitumor and antivirus, and then has great values in the development of pharmaceutical and industrial production. In this study, comprehensive statistic analyses on the diversity and distribution of urushiol in the family were carried out based on urushiol data of different groups of Anacardiaceae extracted from literatures. Meanwhile, the origin and evolution of urushiol in the family were inferred using the nuclear ETS and the chloroplast genes rps16 and trnLF sequences. The results show that: (1) the urushiol has a high diversity and has great variation in its phenol and R chain. (2) Urushiol is only found in the Anacardioideae and is an important feature of the subfamily. (3) Reconstruction analysis of ancestral traits based on the structure of urushiol phenol and R chain indicates that urushiol from the lacquer family evolved from catechol to resorcinol, while the pentadec(en)yl group of urushiolR chain evolved to the heptadec(en)yl group.