Yellowish urine may be caused by physiological factors, urinary tract infections, liver diseases and other factors. 1. Physiological factors: urine concentration, carrot consumption, oral vitamin B and other factors, may lead to the color of urine becomes dark yellow, but no other abnormal performance, belong to physiological factors, do not need special treatment. 2. Urinary tract infections: cystitis, for example, may be related to poor hygiene, long time holding urine factors, the presence of purulent substances in the urine, can make the urine yellow, accompanied by pain in urination, urinary frequency, urinary urgency and other related symptoms. 3. Liver disease: for example, hepatocellular jaundice, may lead to abnormal bilirubin metabolism, will enter the urine, will make the color of urine become dark yellow, may also be accompanied by itching, yellow skin and other symptoms. Urine yellow, and there are other abnormal manifestations, also exclude physiological factors, may be the existence of disease factors, should also seek medical examination and treatment.