Malformation tumor, also known as renal vascular smooth muscle lipoma, is a benign tumor. There is some controversy in the treatment of renal malformation tumor. The efficacy is closely related to the size of the mass and the accompanying symptoms, and the treatment is as follows: 1. Observation: Tumor <4cm can be left untreated, but close follow-up is required. Some tumors can not continue to increase in size for many years. ＜For asymptomatic tumor <4cm, follow up once a year; for asymptomatic tumor >4cm or with mild symptoms, follow up once every six months. 2.Embolization arterial embolization should be considered first for cases of bleeding: according to experience the volume of tumor does not decrease after embolization, but bleeding can be stopped. Super-selective renal artery branch embolization is mostly used to protect part of renal function. 3.Surgery to preserve renal unit: the risk of rupture and bleeding occurs in tumor >4cm rises, and surgery can be considered. ＜If the tumor is <5cm, enucleation is feasible, especially for tumors at the edge of kidney. However, some tumors have inconspicuous envelope, irregular shape and unclear interface, so enucleation is unsafe and partial nephrectomy can be performed. 4.Nephrectomy: Nephrectomy is feasible for huge renal malformation tumor; if the lesion is bilateral, more consideration should be given to the preservation of renal function; in a few cases, there may be local and lymph node invasion, and even the tumor embolus invades the large vein, showing malignant behavior, and radical nephrectomy should be performed. 5.Nephron transplantation or hemodialysis: Only for patients with bilateral lesions leading to renal failure or tumor rupture and bleeding and must undergo bilateral nephrectomy. Not every person has the same condition after the disease, it is necessary to make a treatment plan according to the detailed situation of the examination and take effective treatment in time.