A two-years cross-sectional study of schistosomiasis mansoni in a rural community of the county of Itanhomi (State of Minas Gerais, Brasil) was performed. Particular attention was given to morbidity rates in 1,480 inhabitants, sanitary facilities, and intermediate host infection rates, in view of a later longitudinal work at the same region. Figures of prevalence over 60 percent in 1973 and 1974, and a 5.8 percent of patients with severe forms of the disease (liver and spleen enlargement), suggest the high endemicity of schistosomiasis in the area. Distribution of the infected population as to the clinical forms of the disease were as follows: 61.7 percent with subclinical infections; 32.5 percent with hep ato intestinal form; and 5.8 percent with liver and spleen enlargement (including 0.8 percent of teenagers with delayed sexual maturation and physical growth). Strong correlation was observed between severe cases in 11 to 15 years old males and greater exposition to the intermediate host (Biomphalaria glabrata) foci, and higher infection rates as shown by the average number of eggs of S. mansoni per gram of faeces.