Rio Grande do Sul (RS), in South Brazil, with about 10 million inhabitants, is known for its agricultural activities and consequent increased human exposure to toxic agents. Patients with de novo acute myeloid leukemia (AML) were included based on information retrieved from all referral hospitals in RS between 1996 and 2000. A total of 532 patients were registered. Median age at diagnosis was 42 years. The estimated annual incidence was 1.11 cases/100,000 inhabitants/year. There was an estimated incidence of 0.5-1 case per 100,000 inhabitants up to the age of 45 years, and of 3.5 cases per 100,000 inhabitants aged 70 years and older, with no geographical clusters. The mean 5-year survival rate was 17% for all cases. There was an increased number of M3 cases, as already described for individuals of Latin-American and the mortality rate was similar to that described in the literature.