Abstract A multiresidue technique was developed for the analysis of 17 organochlorine compounds in cheese: α-hexachlorocyclohexane (α-HCH), β-HCH, γ-HCH, δ-HCH, aldrin, dieldrin, endrin, heptachlor, heptachlor epoxide, chlordane, o,p′-…(o,p′-DDT), p,p′-DDT, o,p′-…(o,p’-DDD), p,p′-DDD, o,p’-… (o,p′-DDE), p,p′-DDE, and the fungicide hexachlo-robenzene. In this technique, the fat, previously extracted from the cheeses, was subjected to 2 cleanup and extraction methods: with H2SO4, for acid-resistant organochlorine pesticides, and with KOH-ethanol. The behavior of the compounds in both treatments enabled us to identify the organochlorine pesticides in cheese. The precision (repeatability and reproducibility) and accuracy of the technique were validated.