10.22376/ijpbs.2019.10.1.p1-12 Volume 10 Issue 2 2019 (April-June) Essential Oils (Eos) are unique natural volatile and odoriferous plant products. Eos are used in perfumery as well as in therapeutic industries. Essential oils play multiple roles such as defence, hormonal activities, initiate cellular regeneration, and work as protective against fungal, viral, and animal foes. Eos are composed of volatile compounds and these compounds mainly belongs to the group terpenoids and its derivatives lessThan i greaterThan . Pogostemon lessThan /i greaterThan spp. belongs to the family Lamiaceae which are well known for a range of volatile constituents. But, most of them are underutilized. In this juncture, the present study is conducted to extract, identify and compare the essential oils of lessThan i greaterThan Pogostemon benghalensis lessThan /i greaterThan (Burm.f.) Kuntze. and lessThan i greaterThan P. cablin lessThan /i greaterThan (Blanco) Benth. The leaves of the lessThan i greaterThan Pogostemon cablin lessThan /i greaterThan (Patchouli) are widely used for the large scale production of Patchouli oil, which is an important and unique commodity in the fragrance and medicinal industry. Fresh leaves of the plants were used for the isolation of essential oil. The leaves were subjected to steam distillation in a Clevenger type apparatus for the extracted of oil. The isolated oils were analysed by GC -FID followed by GC-MS. From analysing the chromatogram, 41 and 36 volatile compounds were identified from the leaf essential oil of lessThan i greaterThan P. benghalensis lessThan /i greaterThan and lessThan i greaterThan P. cablin lessThan /i greaterThan respectively. Patchouli alcohol and α-Cadinol were the major components in the oils oil of lessThan i greaterThan P. benghalensis lessThan /i greaterThan and lessThan i greaterThan P. cablin lessThan /i greaterThan respectively. These oils contained mainly sesquiterpene and oxygenated sequiterpene hydrocarbons. The difference in the quality and quantity of compounds present in the oils of selected lessThan i greaterThan Pogostemon lessThan /i greaterThan species suggests their significant role in various therapeutic potentialities. Based on the qualitative and quantitative analysis, the oils from lessThan i greaterThan Pogostemon benghalensis lessThan /i greaterThan and lessThan i greaterThan Pogostemon cablin lessThan /i greaterThan can be used in perfumery industry and developed for the production of novel natural medicine. PRADEEP .D.P AND K. MURUGAN Essential oil, Pogostemon, GC-FID, GC-MS, α-Cadinol 61-67