Fumigant toxicity of four plant essential oils (muguet flower, patchouli, pennyroyal, spearmint) were tested against the adults of westem flower thrips, Frankliniella occidentalis. Among them, pennyroyal and spearmint oils showed 100% mortality at 1 ㎕/45 ㎖ air dose. Through the constituent analysis using GC and GC-MS, we confirmed that main constituents of pennyroyal oil were pulegone(100.0%), and spearmint oil were β-myrcene(3.5%), limonene(12.1%), carvone(85.4%). Among them, carvone and pulegone showed 100% fumigation at 1 ㎕/45 ㎖ air dose, respectively. It can concluded that two oils aloe potential control agents against F. occidentalis.