The frequency of trichinosis was determined in 300 dead persons, residents in the provinces of Concepción and Arauco, and requiring necropsy at the Servicio Medico Legal of Concepción. Diaphragm muscle samples were taken from June 1996 to March 1997. The diagnosis was made by trichinoscopy and artificial digestion techniques. Five samples (1.67%) were positive. There was not differences between sexes. Positive cases were found mainly among 30 to 49 years old people belonging to middle-lower class. Both diagnostic techniques showed different sensitivity as a consequence of the parasitic load and on the contrary, the artificial digestion was less sensitive when the cyts were fully calcified.