Ex situ conservation, the protection of organism outside of their native habitats is an important strategy towards reaching the goal of biodiversity conservation. Amongst the various approaches of ex situ conservation botanical gardens hold an important position. With an inherent objectivity of conservation they are important ingredient of research and education. Since the mid-1970s public gardens world- wide has been active in the development of plant conservation programs often involving the cultivation and long-term maintenance of plants or populations of threatened species. Botanical gardens collectively exhibit an extremely diverse world flora. This article attempts to illustrate the importance of botanical gardens in the conservation of plant diversity along with the associated educational and research benefits, taking into account the flora of Botanical garden, situated at University of Delhi, Delhi, India.