A prospective and cross-sectional study was carried out in various communities in Kwara State, Nigeria, to access the status and implications of urinary schistosomiasis among schoolchildren. Of 425 pupils examined in nine communities, 193 (45.4%) were infected. Infection rates for boys (44.7%) and girls (47.9%) were not significantly different (p greater than 0.5). Children between 11 and 13 years of age had the highest incidence rates (33.6%). However, the percentage of children (25.9%) excreting at least 1000 eggs per 10 ml of urine sample during their first decade of life was significantly higher (p less than 0.01) than for older pupils. The health implications of schistosomiasis acquired early in life, as in this study, are highlighted in the discussion.