Foamy urine that disappears in 30 minutes alone is not a simple way to determine whether it is normal or abnormal. Under normal circumstances, the urine may produce foam, most of which will disappear in about 10 minutes. If the urine foam is more, not easy to disappear, need to consider is caused by pathological factors. Urine routine examination is needed to clarify whether there is proteinuria, urine sugar, urine ketone bodies, urine leukocytes, urine bilirubin and so on. In general, there are a variety of metabolites in the urine, these metabolites have different surface tensions, and will form foam of varying sizes after discharge. With foamy urine consider whether there are various types of glomerulonephritis, pyelonephritis, diabetic nephropathy, hypertensive nephropathy, IgA nephropathy, nephrotic syndrome and so on. At the same time, pay attention to the blood sugar and white blood cells in the urine. Detailed examination should be carried out in hospital in time to clarify the cause and avoid complications.