The presence of fascioliasis was assessed in four Andean communities using an enzyme-linked immunosorbent assay (ELISA) test to measure antibodies against Fasciola hepatica excretion-secretion antigens. Six percent (9 out of 150) of the individuals in one community were ELISA-positive for these antibodies. Fecal samples from two of the ELISA-positive individuals contained F. hepatica ova. All of the ELISA-positive cases, except for one, were children within the ages of 9 to 12 years.