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Insecticidal property of essential oils obtained from 6 plants essential oils namely;dill (Anethum graveolens Linn.), star anise (Illicium verum Hook.f.), lemon grass (Cymbopogon citratus (Dc.ex.Nees)), clove (Syzygium aromaticum (Linn.) Merr&L.M.Perry), cinnamon (Cinnamomum bejolghota (Buch.-Ham.)) and betel vine (Piper betle Linn.) against adult of brown planthopper (Nilaparvata lugens (st(a)l);BPH) was evaluated by using direct spray method.Those plant essential oils at the concentration of 0.2% in corporate with Tween-20, petroleum oil and white oil were applied for 5 ml by Potter's spray tower under 10 lbf/sq in.Amount of 10 BPH adults per replicate were used for the bioassay with 5 replications in CRD.The mortalities of BPH were observed at 6 hrs after treatment.The results showed that essential oils of lemon grass and star anise in corporate with petroleum oil were the most toxic to the BPH, caused 72.0 and 68.8% mortality, respectively as well as the both essential oils in corporate with Tween-20 caused 61.3% mortality.Whereas, all essential oils in corporate with white oil showed relatively low 22.4% mortality.The comparative study presented that the insecticide (imidacloprid) at recommendation rate and double rate caused only 51.4 and 52.2% mortality, respectively.The result revealed the imidacloprid (recommendation rate) + petroleum oil and imidacloprid (recommendation rate) + Tween-20 showed highest effective in controlling the BPH showed 85.6 and 88.7% mortality, respectively.Beside, essential oil of lemon grass at 0.2% in corporate with petroleum oil showed remarkably BPH mortality of 72.0%.