Abstract: The essential oil from Rhododendron thymifolium Maxim. was abstracted by steam-stilling and analyzed by capillary GC-MS method. By capillary chromatography , more than 83 peaks were isolated , and 77 compounds of them were identified , the identification rate was 98. 63 %. The relative percentages of the constituents were determined by GC method , and the main chemical component parts of the oil were 5-Hydroxy-2-methyl benzaldehyde ; 22Fluorophenyl isocyanate ; Cyclohexanone , 5-ethenyl-5-methyl-; Cyclohexane , 1-ethenyl-1-methyl-; Naphthalene , decahydro-4α-methyl-; β-Elemenone ; Naphthalene , 1 , 2 , 3 , 5 , 6 , 7 , 8 , 8α-octahydro- and
etc. The study provided solid and scientific proof for the further development of Rhododendron thymifolium Maxim.

Key words: Rhododendron thymifolium Maxim., Essential oil, GC-MS