Newly moulted fourth and fifth instar nymphs of Schistocerca gregaria Forskal were exposed to Precocene 11 and Juvenile Hormone III (40 lig per live body weight). The effects of Precocene treatment might be attributed to the lack of JH release, which caused reduction in the haemolymph protein and lipid of male and female adults emerging from treated 5th instar ny‌mphs. Also, JH III inhibited both of protein and lipid in the adult female haemolymph when treated on 4th instar nymphs. The inhibition of protein synthesis and the substantial suppres‌sion of lipids by JH III and Pll in gregarious locusts could probably sup‌press long-distance migratory flights; thus, JH III and Pll could conceiva‌bly be used to prevent migration of S.gregaria from their recession areas into farmland, which would allow an alternative strategy in locust con‌trol.