This study aimed to evaluate the effect of menthol oil, camphor oil and their mixture against the green leafhopper, Empoasca decipiens Paoli (Hemiptera: Cicadellidae) in laboratory and estimation of LC₉₀ to apply it under semi-field condition. The results showed that the mixture of the two oils was more effective than each essential plant oil alone where LC₅₀ was 37.86 ppm while it was 182.34 ppm and 242.80 ppm for menthol oil and camphor oil, respectively. LC₉₀ values were 463.12 ppm, 962.36 ppm and 1128.05 ppm for the mixture, menthol oil, and camphor oil, respectively. When LC₉₀ was applied in the semi-field experiment, also the mixture of camphor and menthol oil was the most effective than each plant oil alone which recorded 50% mortality while menthol oil recorded 41.03 % and camphor oil recorded 35.90%.