We reviewed 530 patients treated with anatrophic nephrolithotomy during a 14.5-year period. Significant postoperative renal bleeding occurred in 34 cases (6.4 per cent). The average postoperative blood transfusion requirement in this group was 5,279 cc. Bleeding patients were significantly older and they had worse renal function compared to the nonbleeding group. If bleeding did not begin immediately it usually started 5 to 8 days postoperatively. Bleeding dyscrasias were identified in 6 patients and correction allowed nonoperative management in 4. Epsilon aminocaproic acid was helpful only in the treatment of patients with slow, lower volume bleeding. Eight patients required 9 open renal explorations to control bleeding. Two arteriovenous fistulas and 1 false aneurysm were identified. An attempt at angiographic embolization of an arteriovenous fistula was unsuccessful. Only 1 patient required a nephrectomy (1 of 34 or 2.9 per cent) and there was no mortality. A treatment plan for this complication is described.