Abstract The composition of the essential oil of the aerial parts of the Santolina chamaecyparissus L. plants collected from the campus of CIMAP field station Kodaikanal (southern hills) was analyzed by GC and GC/MS. The oil yield obtained upon hydrodistillation was 1.1% (v/w) on fresh weight basis. The analysis of the oil led to the identification of 25 constituents totaling 97.4% of the oil. The identified constituents included monoterpene hydrocarbons (30%) oxygenated monoterpenes (56%), sesquiterpene hydrocarbons (10.6%) and oxygenated sesquiterpene (0.8%). The major constituents of the oil were artemisia ketone (32%), 1,8-cineole (15.6%) and myrcene (14.5%).