The plants of the Trigonostemon genus (Euphorbiaceae family) comprising about 50 species are mainly distributed in tropical and subtropical Asia. Chemical studies on this plant genus have led to the discovery of about 200 structurally diverse compounds in the last two decades, some of which have shown promising biological activities. Diterpenoids and alkaloids are the major and most important components of Trigonostemon plants, and are also the hot topics in synthetic chemistry. This review was attempted to provide the timely and comprehensive coverage of the chemical and biological studies on Trigonostemon plants, and especially to focus on the recent research progress.