The use of pesticides in agriculture has grown dramatically over the last decades. Environmental exposure of humans to agrichemicals is common and results in both acute and chronic health effects. In this study, the DI-SPME technique coupled with GC/ECD was developed for trace determination of nineteen chlorinated pesticides in tomato samples by using a 100 μm PDMS fiber. Experimental parameters, such as extraction time, extraction temperature, stirring and salting out, were evaluated and optimized. The LODs ranged from 0.5 to 8 4g Kg-1; the LOQs from 5 to 30 4g Kg-1. A linear response was confirmed by correlation coefficients ranging from 0.97 to 0.9985. The developed method was further tested analyzing real samples purchased on the network of the Italian large distribution. The samples resulted free from detectable residues of the analyzed pesticides. SPME has been shown to be a fast extraction technique which has several advantages such as solvent-free extraction, simplicity and compatibility with the chromatographic analytical system.