This is a basic descriptive research with a non-experimental methodological design. The objective of the research was to determine the presence of residues of the organophosphorus pesticide methamidophos in Solanum tuberosum (potato) in the sector of Cuchupuquio - Viques, using a sample of 5 kg of potato from each of the farms, where the instrument was a survey validated by experts. The results showed that of the 15 samples analyzed, 2 (13.3%) were positive for methamidophos and 13 (86.7%) were negative, with a positive reaction of yellow spots on a light brown background