cis-Jasmone is a plant volatile known to have roles as an insect semiochemical and in inducing plant defence. It was evaluated in laboratory and field trials for control of cereal aphids. In an olfactometer bioassay cis-jasmone was repellent to alatae of the grain aphid, Sitobion avenae (Fabricius) (Homoptera: Aphididae). Moreover, wheat, Triticum aestivum (L), seedlings sprayed with formulated cis-jasmone 24 h previously were less susceptible to attack by S. avenae than control plants. In field simulator studies, significantly fewer alate S. avenae settled on cis-jasmone-treated plants over a 24-h period. In addition, the intrinsic rate of population increase, r(m), of S. avenae apterae was reduced on cis-jasmone treated seedlings. In a series of small-plot experiments conducted over four years, cis-jasmone applications reduced cereal aphid populations infesting wheat in the field.