Diabetic patients do not always have foam in their urine. For diabetic patients with a long history of diabetes, if you find increased foam in the urine, it indicates that there may be albumin leakage in the urine, which is clinically referred to as proteinuria, and positive urine protein in diabetic patients indicates the presence of diabetic nephropathy. Diabetic nephropathy is a type of diabetic microcirculatory disease, characterized by an increase in urine protein, which is manifested in the appearance of increased urine foam. Therefore, once diabetic patients have increased urine foam, they must get their urine protein checked. If there is no protein in the urine, diabetic patients’ urine should be relatively clear without too much foam. Therefore, diabetic patients do not always combine foam in urine, if there is foam must be taken seriously, there may be diabetic nephropathy.