The selective toxic insecticidal properties of pirimicarb, carbaryl and methamidophos to the green peach aphid,Myzus persicae(Sulzer), and its predators,Coleomegilla maculata lengi(Timberlake) andChrysopa oculata(Say) were studied. Pirimicarb was less toxic than carbaryl and methamidophos toC. maculataandC. oculataand more toxic to aphids. The selectivity ratio for pirimicarb indicating selectivity favoring the predators was ca. 4000:1.