The effect of surgery, postoperative combination chemotherapy and postoperative radiotherapy was evaluated in subcutaneously implanted Wistar/Furth rat Wilms’ tumor. Four groups were studied. Group A (controls, no treatment given) had a median survival of 44 days. Group B (surgical excision of the primary tumor on day 14 after implantation) showed a median survival of 77 days, with 40% tumor-free long-term survivors (sacrificed on day 175). Group C (excision followed by chemotherapy consisting of vincristine, actinomycin D and adriamycin) had a median survival of 61 days with 35% tumor-free long-term survivors. Group D received the same postoperative chemotherapy as well as radiotherapy and had 55% tumor-free long-term survivors. This tumor may serve as a treatment model for some human Wilms’ tumor cases who do not respond well to current therapies.