As part of the research on the nutritional physiology of the brown rice planthopper, the nutritive value of sugars for larval growth was studied. Hatched larvae were reared on an MED-I diet supplemented with one of the following sugars : sucrose, glucose, maltose, fructose, raffinose, or trehalose at concentrations of 5%. All larvae died within several days on diets supplemented any one of these sugars except sucrose. Larvae reared on diets containing glucose, fructose, or maltose grew to adults when the diet was supplemented with 1% sucrose, while those reared on raffinose or trehalose with an additional 1% sucrose still died within several days. When the larvae were reared on diets containing sucrose as the sole sugar, adult emergence depended on the sucrose concentration, which ranged from 3% to 50%. The shortest nymphal period was observed on the diet containing 5% sucrose.