Four children with anuria due to occlusion of both ureters by calculi are presented. A plain film of the abdomen revealed faintly radiopaque urinary. calculi bilaterally in three patients. In the fourth case, one calculus was visualized in the right ureter, but further contralateral expiration showed an obstructing ureteral calculus in the left ureter as well. It is concluded that in children with acute anuria, the possibility of bilateral ureteral obstruction due to calculi should be the physician's first consideration.