The aim of the study was to determine the frequency of external parasites in guinea pigs (Cavia porcellus) during the rainy and dry seasons in family-commercial farms in Oxapampa, Pasco, Peru. Also, aimed to identify the ectoparasites and to determine the association between seasons and the presence of external parasites. A total of 230 animalswere evaluated per season. Ectoparasites were collected using three techniques: skin scraping, transparent tape, and fine comb. The frequency of parasitism was 70.9 ± 5.9 and 83.0 ± 4.9% for the rainy and dry seasons respectively. Five species of Acariformes and three species of Phthiraptera were identified, and the most frequent were Chirodiscoides caviae and Gliricola porcelli. Significant association was found between the season of the year and the presence of external parasitism (p<0.05).