Proteinuria means that for some reason protein in the body is excreted with the urine. The appearance of urine is characterized by increased urine foam, which is not easy to dissipate; urine protein is seen to be positive in routine urine examination. Common causes include fever, excessive exercise and other physiological reasons, but also can be seen in glomerulonephritis, urinary tract infection and other pathological factors. Physiological proteinuria is due to the body for internal and external environmental stimuli, resulting in the body to appear transient proteinuria, more common are strenuous exercise, high protein diet, adolescent growth and development process of transient proteinuria and so on. This type of proteinuria, with the elimination of the stimulus, usually return to normal. Pathological proteinuria is usually due to glomerulonephritis, urinary tract infections, urinary stones, urinary tract tumors, diabetic nephropathy and so on. This type of proteinuria needs to go to the nephrology department of regular hospitals and be treated under the guidance of professional doctors. Therefore, patients with proteinuria should go to the hospital to find out the cause and follow the doctor’s instructions to avoid delaying the condition.