Diabetic nephropathy is one of the microvascular complications of diabetes mellitus, which has an insidious onset and progresses slowly. In the early stage, there can be no uncomfortable symptoms, and many patients realize the seriousness of the problem only when protein appears in the urine or blood creatinine is already elevated, therefore, early detection is only possible through regular monitoring. A more authoritative method to screen for early diabetic nephropathy is the 24-hour urine microalbumin quantification. If the 24-hour urine microalbumin quantification is less than 30mg in normal people, and if the 24-hour urine microalbumin quantification is between 30mg and 300mg for two consecutive times within six months in diabetic patients, except for other reasons, it belongs to early diabetic nephropathy; if the 24-hour urine microalbumin quantification is more than 300mg, it enters into clinical diabetic nephropathy, and the urine routine can show protein at this time. Another method is to directly draw blood to determine the urine microalbumin/creatinine ratio, which is a relatively simple method, but more expensive, and this test is not yet carried out in our hospital. The method of collecting a 24-hour urine specimen: After urinating at 7:00 a.m. on the first day and again at 7:00 a.m. on the next day, collect all the urine during that time (the urine at 7:00 a.m. on the first day is not recorded, while the urine at 7:00 a.m. on the second day must be recorded), mix it well, measure the total urine volume with a measuring cup and record it, and then send a small cup of urine to the hospital for testing. Consult your doctor when the results are available. If the indicator is normal, it should also be monitored annually and whenever necessary.