Essential oils isolated from the branchlets of two populations of Cupressus arizonica Greene (Cupressaceae) growing in Uttarakhand Himalaya (India) were analyzed by GC and GC/MS in order to determine the variation in composition of their constituents. A total of 36 constituents representing 90.7â92.2% of the total composition have been identified in two locations. In the oils, monoterpenoids (90.0â90.7%) were the principal class of the components (oxygenated monoterpenes, 46.3â52.6%; monoterpene hydrocarbons, 37.4â44.4%), while sesquiterpene hydrocarbons found in lesser amounts (0.7â1.5%). Umbellulone was identified as the major constituent of the essential oils, which ranged from 20.9 to 30.6%. The other main constituents in the essential oils were found to be limonene (8.0â12.9%), Î±-pinene (7.1â8.1%), sabinene (6.6â7.0%), p-cymene (3.2â5.9%) and terpinen-4-ol (4.2â5.6%). In summary, the characteristic of C. arizonica essential oil from Uttarakhand Himalaya (India) is due to the presence of umbellulone and limonene in higher amounts.