Foamy and smelly urine can be caused by physiological factors, urinary tract infections, diabetes and other factors. 1. Physiological factors: such as urine concentration or dietary factors, may lead to urine foam with odor, but no other urinary abnormalities, should increase the amount of drinking water, and improve the daily diet, more urination, can autonomy to return to normal. 2. Urinary tract infections: cystitis, for example, may be related to drinking too little water, do not pay attention to physiological hygiene, can make the presence of purulent secretions in the urine, leukocytes and other substances, which can make the urine foamy and foul-smelling, accompanied by pain in urination, frequent urination and other symptoms. 3. Diabetes: It may be related to heredity and poor dietary habits. When blood sugar continues to increase, it may lead to ketoacidosis and diabetic nephropathy, which will lead to increased foam in the urine, accompanied by obvious odor, and there will also be fatigue, drinking and urinating. Foamy urine with odor and other abnormal manifestations, may be the existence of disease factors, it is recommended to consult a doctor for appropriate examination and treatment, so as not to delay the condition.