An insecticidal composition in the form of microemulsion comprising: about 1% to about 25%m/m Chlorpyriphos about 5% to about 15% by weight aromatic hydrocarbon or vegetable oil ester about 1% to about 5% by weight co-solvent about 15 to about 40% by weight surfactant and about 15 to about 30% by weight co-surfactant.