If the increase in kidney volume is compensatory, it is usually harmless. If it is pathologically enlarged, oliguria and anuria may occur, which is usually more harmful. 1. Compensatory enlargement is not harmful: one side of the kidney is injured or one side of the kidney disease leads to resection, the other side of the kidney may appear compensatory enlargement. This kind of enlargement belongs to physiological enlargement, which is generally not harmful to human body. 2. Pathological enlargement: if ureteral stones, ureteral occupation, will lead to renal obstruction and fluid phenomenon, kidney volume increases, affecting the timely discharge of urine, usually more harmful, this time should be timely removal of obstruction factors. In the early stage of diabetic nephropathy, the kidneys are in high filtration state and the volume of kidneys increases, at this time, active treatment should be carried out to prevent the disease from progressing. If the kidney volume increases due to chronic renal insufficiency, the toxins can not be eliminated from the body through urine and so on in the late stage, the harm is also greater. Once the increase in renal volume is determined to be a pathological factor, in order to avoid the late hidden danger, it is recommended to go to a regular hospital in time, under the guidance of a specialist physician treatment.