Residue analysis of pesticides in the lettuce: "Lactuca sativa" is examined. A multiresidue method for the identification and measurement of a group of organophosphates used as insecticides in horticulture is developed. The problems of obtaining a reasonable recovery after clean-up when dealing with this variety are investigated. Clean-up was effected using Sep-Pak C 18 and Bond Elut 2 OH (Diol) cartridges. The results were good and demonstrate that it is possible to apply this multiresidue method to organophosphorous pesticides. Further research will be done in order to determine whether these and other compounds can be isolated in the varieties "Endivia" and "Cicorium intybus". The aim of the investigation was to isolate organophosphates used in new pesticides, with specific regard to lettuce. We investigated on Diazinon, Chlorpyriphos-methyl, Malathion, Parathion, Quinalphos, Ethion, Azinphos-methyl, Azinphos-ethyl, Phosalone. The interest in these residues in lettuce is justified by it widespread application in the Veneto region.