The successful removal by extracorporeal hemofiltration of adult parasites from patients affected with hepatosplenic disease caused by Schistosoma mansoni and Schistosoma japonicum stimulated the development of an operation for Schistosoma haematobium. Although based on similar principles, it is a simpler procedure resembling the catheterization used frequently in radiographic vascular visualization. In Iran, three male patients with active urinary schistosomiasis were selected for extracorporeal hemofiltration. The operations were performed and were technically successful; however, no worms were found in the filters. The failure to capture the worms, which may be attributed to various factors, has served as a stimulus for further studies on the location and physiologic response of the parasite.