Renal agenesis is born with two kidneys, but one of them has atrophied away and has no function, while the other kidney is normal in size. One kidney can also excrete the nitrogenous metabolic waste and urine produced in the body, and the levels of urea nitrogen, creatinine and uric acid in the body are completely normal and do not affect the quality of survival of patients. However, patients with one kidney alone must pay special attention to avoid the application of nephrotoxic drugs, any operation on the kidney, overexertion, etc. Also, pay attention to low-fat, low-salt, high-quality, low-protein diet as the mainstay of the diet, and check the body every six months to a year to check renal function and urinary routine, etc. Once abnormal renal function occurs, it is recommended to actively preserve the kidney for treatment.