For many thousands of years, there are many medicinal plants which have been used to cure diseases throughout the world. One such plant is Tulsi (Ocimum sanctum) which have several medicinal properties .Tulsi plant is used not only in Ayurveda and Siddha but also in Greek, Roman and Unani systems of medicine. Tulsi is used as anti-asthmatic and anti-kaphic drugs. It is also used in treatment of fever, bronchitis, arthritis, convulsions and in periodontitis it influences cytokine production and has an immune modulatory effect .Tulsi extracts are used as oral rinses. This article outline the present knowledge of pharmacological and other studies of this plant and its various possible applications in medicine and to pave the way for future studies in its applications in medicine.