Baby urination yellow may be certain physiological phenomenon, may also be the manifestation of certain diseases symptoms, such as neonatal jaundice, urinary tract infection, etc., should be timely consultation to identify the cause. 1. Physiological factors: if the baby usually do not have the habit of drinking water, making insufficient water intake, resulting in urine concentration, which may appear yellow urine. It is also possible that the baby over-eating food containing yellow pigment, such as pumpkin, carrots, etc., the urine color will also be obviously yellow. 2. Pathologic factors: (1) If the newborn baby’s urine is yellow, you need to consider whether it is caused by neonatal jaundice, such as ABO hemolysis, Rh hemolysis, congenital biliary atresia and other disorders, can cause yellow urine. (2) Urinary tract infection is an infectious disease caused by pathogens invading the mucous membranes or tissues of the urinary tract, which can cause urinary tract irritation symptoms such as frequent urination, urinary urgency and painful urination, and may also lead to pus at the urethral opening, cloudy urine, and yellowing of urine. Causes of yellow urine in children are more reasons, and other factors can not be ruled out. Parents are advised to bring their children to the doctor in time if physiological causes are excluded, so that the doctor can clarify the causes and give targeted treatment.