Diabetic patients can have any kind of renal disease, the most characteristic of which is diabetic glomerulosclerosis, one of the most important microvascular complications in diabetic patients. This lesion may be present soon after the onset of diabetes, but it does not show much in the early stages. Symptoms do not manifest until 10 years after the onset of the disease, initially with protein in the urine, which may be accompanied by white blood cells and tubular patterns. As the disease gradually worsens, renal function decreases. In the later stages of the disease, protein in the urine gradually increases and 3-4 grams or more of protein can be lost daily, causing swelling and uremia. The main changes in the early stage of diabetic nephropathy are renal hyperperfusion, hyperfiltration and increased kidney volume. This stage can be reversed by treatment, but once it enters the clinical proteinuria stage the disease is irreversible. Therefore, the prevention and treatment of early diabetic nephropathy is particularly important. Proteinuria is one of the manifestations of kidney damage. When glomerular disease is present, capillary permeability increases and the amount of filtered plasma protein, mainly albumin, increases. At present, the clinical diagnosis of early diabetic nephropathy is mainly based on the increase of urinary albumin excretion rate, in the basic state of urinary albumin excretion in 20-200 micrograms/min, no urinary tract infection, no heart failure, no hypertension, or hypertension has been reduced to normal with medication, within six months, the basic urinary albumin excretion for three consecutive times at this level can be diagnosed as early Diabetic nephropathy. Strict control of blood sugar is the key to prevent and reduce early diabetic nephropathy. According to recent studies, the application of insulin pump to strengthen the long-term control of blood glucose at normal level can significantly reduce the rate of microalbumin urine excretion, and some of them can be reversed and turned into normal albumin urine excretion rate. Therefore, urinary albumin is highly correlated with good or bad glycemic control. Hypertension is also an important risk factor for the development of diabetic nephropathy. If blood pressure is controlled at the ideal level (125/85 mmHg) for a long time, the rate of urinary albumin excretion can be reduced. Excessive protein intake, especially the large molecular particles of vegetable protein, can aggravate the filtration damage of the kidney and accelerate the sclerosis of glomerular capillaries. Although a low-protein diet is beneficial to protect the kidney, it is too early to be used as dietary treatment for early diabetes. The choice of which diet is more conducive to renal protection in diabetes has a very important status. In the traditional diet, the main source of protein is vegetable protein, which has a high content of non-essential amino acids and low bioavailability, which can increase the burden on the kidneys. Animal protein, on the other hand, has a high content of essential amino acids, the highest utilization rate and the best nutritional value. The nutritional value of protein from animal foods such as milk, poultry and eggs, and aquatic products is the best, which is beneficial to protect the kidneys. Early diabetic nephropathy is a high risk factor for turning into clinical diabetic nephropathy, which means it can easily turn into clinical diabetic nephropathy. As long as the strict control of diabetes, so that blood sugar drops to normal level, at least to very close to normal level, blood pressure control at ≤ 125/85mmHg and low protein diet can delay, or even prevent its development into clinical diabetic nephropathy.