There is no clear relationship between the CT value of the kidney and tumor stage. In general, CT values of the kidney are above -100. One should consider a vascular smooth muscle lipoma or a staggered tumor, which is a benign tumor. If the CT value is between -10 and 20, it is usually considered a renal cyst. Enhanced examination should be performed to see if there is a blood supply to rule out a tumor. If the CT value of the kidney is between 20 and 40, it is usually considered a substantial occupancy. At this point, an enhancement modality is needed to clarify the benign or malignant nature. If a renal tumor is found during CT or ultrasound examination of bilateral kidneys, the patient needs to follow the doctor’s instructions for treatment in time to avoid deterioration of the condition.