The aim of this study was to investigate whether the polymorphisms at the TNF loci are associated with Chagas' disease. We determined the TNFA (positions -308, -244 and -238) and TNFB genotypes in a sample of 85 serologically positive chagasic individuals and in 87 healthy controls from a Peruvian population where Trypanosoma cruzi infection is endemic. Patients were subdivided according to the presence (n= 33) or absence (n =52) of chagasic chronic cardiomyopathy, in order to search for genetic differences associated with this pathological condition. No significant differences either between patients and controls or between asymptomatic and cardiomyopathic individuals were observed with respect to TNFA or TNFB polymorphisms when these were considered individually or as extended haplotypes.