Cassia siamea is a shrub belonging to the Fabaceae family, native of Southeast Asia and better known in folklore medicine, feeding, agriculture and manifacture all over the world including Côte d’Ivoire. C. siamea has recently been shown to have antimicrobial, antimalarial, antidiabetic, anticancer, hypotensive, diuretic, antioxidant, laxative, anti-inflammatory, analgesic, antipyretic, anxiolytic, antidepressant, and sedative activities. Chromone (anhydrobarakol), Chromone alkaloids (barakol, cassiarin A-B), anthraquinones (chrysophanol, emodin), bianthraquinones (cassiamin A-B), flavonoids and phenolics compounds are the main constituents which are reported in this plant. Barakol was identified as the major constituents of C. siamea of leaves and flowers of the world. Due to the easy collection of the plant, it widespread and also remarkable biological activities, this plant has become a worldwide medicine. This review presents comprehensive analyzed information on the botanical, chemical, pharmacological and toxicological aspects of C. siamea. Web sites of Google Scholar, Pubmed and Hinari were searched for articles published. Some scientific data were collected through Scientific Units of Research and Formation (UFR) of the University Felix Houphouet-Boigny of Abidjan.