Infantile congenital insufficiency causes asthenia and cold of the kidney; improper nursing after prolonged diseases results in qi deficiency of the lung and spleen as well as dysfunction of urinary bladder in qi activity; the influence of diseases or improper diet causes internal accumulation of dampness and heat stagnating in the liver meridian, giving rise to the transmission of heat to urinary bladder due to the failure of the liver in smoothing and regulating qi; sudden fright or lack of education from childhood fails to develop good habit of urination; excessive play during the daytime results in deep sleep at night; residential environment is suddenly changed, etc.. All the above factors may give rise to enuresis.