For the purpose of staging sonographical abnormalities induced by Schistosoma mansoni infection in childhood, 536 patients aged 6–15 years underwent extensive sonographical examination. Specific findings of periportal fibrosis were classified in 3 grades and occurred in study patients but not in controls (n = 60). Grade I consisted of echogenic bands usually with a diameter >4 mm that were best visible in the area of the portal vein bifurcation and gallbladder neck. Frequently a continuous U-shaped echogenic structure extended from the left portal branch to the gallbladder bed. Grade II was characterized by echogenic bands usually > 10 mm in diameter around the central part and major branches of the portal vein. In addition to features common to grade II, grade III included streak-like fibrous bands that were not confined to portal vein lumina but extended into the periphery of the liver. Sonographical abnormalities encountered in children with S. mansoni infection differed significantly from those in adults.