Abstract The chemical components of the essential oil obtained from the steam-distillation of Microtoena patchoulii leaves were investigated by GC and GC/MS, and twenty-one compounds were identified. The major compounds of the oil were patchouli alcohol (54.4%), 1-octen-3-ol (21.4%), and Î±-guaiene (2.4%). The composition of M. patchoulii oil is similar to that of commercial patchouli oil, and similar pharmacological effects could be expected when it is used as a substitute for Pogostemon cablin.