The present review article emphasized the pharmaceutical, insecticidal, and therapeutic role of Cassia fistula and its associating species. This is an ornamental plant grown in all parts of India and has a long traditional use in Ayurvedic medicines for the treatment of cough, cold, and sneezing. Plant is a good depository of chemical constituents which display wide array of biological activities such as antipyretic, analgesics, antiseptic, anticancer, antidiabetic, anti-inflammatory, anti-arthritic, antiparasitic, antitumor, antioxidant, chemopreventive, and hepatoprotective. Plant contains important nutraceuticals such as protein 12%, carbohydrate 11.75%, lipid 12%, and free amino acid 1.42%, respectively. C. fistula contains quality antioxidants which provide relieve in ulcers, jaundice, and piles, treat migraine and blood dysentery, treat fever, and relieve from chest and joint pain. The fruit of C. fistula is a good source of Fe and Mn, it is used in treatment of eczema cough, throat troubles, gastric, and liver complaints. Root extract shows tonic, astringent, febrifuge, and strong purgative activities. Plant is also a good source of nutrients, essential oils, antioxidants, and diverse phytochemicals which could be used for production of herbal drugs for the treatment of various diseases.