In the period 1983-1994 a series of seroepidemiological surveys, by using immunodiagnostic tests for trichinosis, was carried out in 138 localities and health institutions from the 13 regions of the country. Thus, a total of 12,882 randomly selected persons, with different sex and age distribution, were submitted to precipitin test and indirect hemagglutination test for trichinosis. One hundred and ninety one (1.5%) persons resulted positive for trichinosis. Higher rates of infection were observed in central and southern Chile. No differences of positivity, according to age sex, but constant increase parallel to age of the individual were detected. The general prevalence rate of infection of 1.5% is in a reasonable accordance with the prevalence of 2.0% found in human corpses in 1992.