Abstract: Objective To evaluate the effects of preoperative chemotherapy for Wilms’ tumor. Methods Thirty-five surgical-ly treated cases of Wilms tumor were retrospectively analyzed, 27 of which received preoperative chemotherapy. Results Af-ter chemotherapy, the tumor volume reduced obviously in 17 cases and adverse effects of the chemotherapeutic agents oc-curred in 15 cases. Subsequent operation was performed in all the patients, of whom 1 died during the operation, 4 had de-layed healing of the incisions and 5 still had decreased leucocytes. Conclusions Chemotherapy before the operation for Wilms tumor can effectively reduce the complications of the operation. Appropriate chemotherapyprotocol and vigorous con-servative drug therapy help prevent the occurrence of adverse effects and complications of the chemotherapy.