Urine foam can be caused by physiological factors, urinary tract infections, diabetes, kidney disease and other factors. 1. Physiological factors: such as dietary factors, strenuous exercise, urine concentration, etc., may lead to the presence of foam in the urine, but there is no discomfort symptoms, eliminating the triggers can be improved on their own. 2. urinary tract infections: for example, cystitis, may be related to long time hold urine and poor hygiene, can make the urine in the presence of a variety of substances, will cause foamy urine, may also be accompanied by frequent urination, urination pain, urinary urgency and other symptoms. 3. Diabetes mellitus: it may be related to heredity and poor dietary habits and other factors, which can make the sugar metabolism in the body abnormal and easily cause foamy urine, and there may also be symptoms such as excessive drinking, excessive urination, excessive eating, and weight loss. 4. Kidney disease: such as glomerulonephritis, may make the function of the kidneys is seriously impaired, will make the presence of protein in the urine, caused by foamy urine, there will also be lower limbs and eyelids swelling and other symptoms. Foamy urine, and the presence of other obvious abnormal symptoms, excluding physiological factors, it is recommended to consult a doctor for examination and treatment, to avoid delaying the condition.