Abstract： Objective To evaluate the therapeutic efficacy of diagnosis and treatment for renal tumor associated with intravascular tumor embolus in children.Methods From 1996 to 2010,total 15patients suffering from renal tumor associated with intravascular tumor embolus underwent treatment in out center,which had extent into the inferior vena cava (IVC) or atrium.Their clinical information was reviewed.Results The most common clinical signs in patients were abdominal mass and hematuria.Symptom that might have been related to the intravascular extension identified was in one patient was considered to be correlated to associated intravascular tumor embolus.15 patients were diagnosed via CT,in which 14 of them were further confirmed via ultrasound simultaneously.13 patients underwent preoperative chemotherapy with dactinomycin and vincristine for 4 to 8 weeks,and regression of intravascular tumor embolus was noted in 6 of them.The resection of tumor was successfully performed in all patients,as well as intravascular tumor embolus,among them cardiopulmonary bypass was conducted for removal of thrombus in one patient.No intraoperative death and perioperative complications were found in this study.The patients received chemotherapy and irradiation according to NWTS4 staging standard and pathological sub-types.9 patients were followed up and 8 patients survived without tumor embolus at present.Among them 1 patient had survived for 5 years since operation.Conclusions Nephrectomy combining with resection of thrombus is the effective approach to treat Wilmg’tumor patient associated with intravascular tumor embolus.