The prevalence of Trypanosoma cruzi infection was studied in a population of 158 children, which ages ranged from 4 months to thirteen years, from Guazú-Cuá department of Paraguarí, which is an isolated community within the endemic area for Chagas'disease. Twelve out of 158 ( 7.6 percent) children yielded positive results for the detection of anti-T. Cruzi antibodies by Elisa. Three cases (1.9 percent) were recorded in children under 5 years of age. These results reveal a high prevalence, according to the criteria establish by the WHO