This article provides an overview on the pharmacological effects, uses of various plant parts, Phytochemical constituents of Tulsi. In India, Tulsi is a plant of religious, cultural and medicinal importance from time unknown. It is also known as holy basil belongs to family Lamiaceae. Each part of the plant that is stem, leaves, roots and the whole plant, flowers is known for its medicinal properties. Tulsi has been found to protect organs and tissues against chemical stress from industrial pollutants and heavy metals, and physical stress from prolonged physical exertion, ischemia, physical restraint and exposure to cold and excessive noise. Tulsi has also been shown to counter metabolic stress through normalization of blood glucose, blood pressure and lipid levels, and psychological stress through positive effects on memory and cognitive function and through its anxiolytic and anti-depressant properties. Tulsi its wide pharmacological uses made it a most sought-after plant for scholars and researchers. In this review article we focus mainly on Cultivation, botanical description, taxonomy, medicinal uses, chemical constituents, pharmacological activities of Tulsi like anti-diabetic, hepatoprotective, analgesic activity, anti-inflammatory were discussed in detail. Various species of genus occimum were also mentioned, with their phytochemical constituents and pharmacological activities. This review article contains cumulative information from various research articles.