We used gas chromatography-mass spectrometry (GC-MS) to analyze total yields and relative composition of the volatile compounds from leaf extracts of Elshoizia cilliata. This species contains 22 compounds. The major constituents of its essential oils are dihydrotagetone (62.7%), $eta$-caryophellene (4.96%), germacrene-d (4.03%), and $alpha$-humulene (1.34%). Compounds in these leaf extracts are remarkably high in dihydrotagetones (40.5 to 81.6%). The total amount of monoterpenoids is 3.17 to 7.03 times greater than that of sesquiterpenoids, and is highly correlated with the level of dihydrotagetone (r =0.97). Seasonal variations are significantly different only for dihydrotagetone (p < 0.0005), but not for the yields of other volatile compounds.