The effects of temperature and concentration of Mipcin (o-cumenyl methylcarbamate) on the imbibed amount by the brown planthopper, Nilaparvata lugens, and the green rice leafhopper, Nephotettix cincticeps, through rice plant and parafilm were examined by the tracer technique during 24 hr period after caging. Dietary and root dipping solutions including the sub-lethal concentration of 0.2 and 1.0 ppm ¹⁴C-labelled Mipcin for the brown planthopper and 1.0 and 10 ppm for the green rice leafhopper were used at ambient temperatures of 25 and 30°C. In the case of the brown planthopper, the imbibed amount through the plant dipped with 1.0 ppm of Mipcin solution at 25°C was lowest, 3.5μl/head/day, and the others were in the range of 6.7-8.2μl. Imbibed amount through parafilm changed from 0.8 to 2.2μl, depending on the concentration and temperature. In the case of the green rice leafhopper, imbibed amount through the plant was in the range of 6.2-8.0μl, almost independent of the Mipcin concentration and temperature. Imbibed amount through parafilm was a minimum of 2.9μl at 10 ppm of Mipcin at 25°C and a maximum of 5.3μl at 1.0 ppm of Mipcin at 30°C.