Residuos de plaguicidas organoclorados fueron determinados en diferentes períodos durante los años 1991 y 1992 en muestras de papas que se comercializan a través del Mercado de la ciudad de La Plata, Argentina. Las determinaciones se realizaron sobre papa entera, pulpa y cáscara. Los plaguicidas organoclorados detectados en mayor cantidad fueron el heptacloro (0,041 ppm) y el lindano (0,030 ppm) con residuos menores a los máximos permitidos internacionalmente. Los mayores residuos fueron detectados en cáscara observándose la existencia de diferencias significativas entre la cáscara y la pulpa. No se observó diferencias significativas en los niveles de plaguicidas detectados en los diferentes períodos estacionales en que se realizó la toma de muestra.Chlorinated plaguicides residues were determinated during 1991 and 1992 in three different periods on potatoes samples commercialized through the Regional Market of La Plata city, Argentine. Determinations were performed on whole potatoes, pulp and peel. The organochlorinated pesticides detected in greater amounts were the heptachlor (0.041 pprn) and lindane (0.030 pprn) which were found at levels lower tham the international maximurn tolerances. Significant higher residues were detected in the peel in comparison to the pulp. Non significant differences in the levels of chlorinated pesticides were observed when sampling was performed at different periods during the year.