Celastrus paniculatus Willd., commonly known as “black oil plant”, “climbing staff tree”, “Jyotishmati” and “intellect tree” is a well-known medicinal plant that has been traditionally employed in Ayurvedic medicine to improve mental function and to treat neurological disorders. The species is well known for its antioxidant, nootropic, antidepressant, anti-inflammatory, and neuroprotective effects. Phytochemical studies have demonstrated the occurrence of alkaloids, sesquiterpenes, flavonoids, and fatty acids, specifically in seeds and seed oil. Current pharmacological research supports several of its established traditional applications, showing prominent effects in memory improvement, anxiety, and models of neurodegenerative diseases. C. paniculatus shows potential in the treatment of arthritis, ulcers, and oxidative stress-linked disorders. This chapter captures the ethnobotanical history of the plant, its phytochemical composition, and pharmacological actions, with emphasis on its role as a natural medicine in neurological and overall health conditions.