Infant urine odor may be urine concentration, urinary tract infection, diabetic ketoacidosis and other factors. 1. Concentrated urine: high indoor temperature, frequent sweating in infants, lack of body fluids, can lead to concentrated urine, it will make the urine appear mild odor, accompanied by dark yellow, cloudy urine. 2. Urinary tract infections: for example, cystitis, may be related to poor hygiene, after the aggravation of the infection, can make the presence of purulent substances in the urine, can lead to smelly urine, accompanied by pain in urination, urinary frequency, urinary urgency and other symptoms. 3. diabetic ketoacidosis: children with diabetes, not timely treatment, the lesions continue to aggravate, may cause ketoacidosis, can lead to urine odor (rotten apple flavor), may also be accompanied by drinking, urination, fatigue, dry skin, depression and other symptoms. Infant urine odor, there may also be other reasons, it is recommended to go to the hospital in a timely manner, improve the examination to clarify the cause of the disease, under the guidance of the doctor to give targeted treatment or treatment.