Over thousands of years, an astounding number of novel medications have been identified from natural sources, many of them based on their use in conventional medical care. It is now well acknowledged that Indian medicinal herbs hold considerable promise for the production of clinically beneficial medications that may even be utilized by allopathic doctors. Cassia is a large genus of around 5000 species of flowering plants in the family leguminaceae / fabaceae. It is extensively distributed over the world, with only 20 species being indigenous to India. In the conventional Indian medical system, this plant has been given credit for a variety of therapeutic characteristics. There are reports indicating its antibacterial activity against a wide spectrum of bacteria, anti-tumor, hepatoprotective antifertility, antioxidant as well as its actions on the central nervous systems. The plants are important sources of tannins, glycosides and flavonoides, linoleic, oleic and stearic acid. This chemical review shows the important bioactive classes of genus Cassia plants extract, including anthraquinones, flavonoids, alkaloids, terpenes, essential oil and sterols.