The heavy odor of urine may be due to symptoms caused by urinary tract infection, phenylketonuria and other conditions, or ketoacidosis, organophosphorus poisoning and other reasons. 1. Urinary tract infection: due to the body produced bacteria and other infections, resulting in the presence of more bacterial metabolites or pus and other substances in the urine, resulting in a heavy odor of urine. 2. Phenylketonuria: mainly due to abnormalities in phenylalanine metabolism, the main clinical features of mental retardation, psychoneurological symptoms, eczema, skin scratching signs and pigmentation loss and rodent odor, etc., due to the lack of phenylalanine hydroxylase enzyme, phenylalanine from the other pathway to produce an increase in phenyl lactic acid and phenylacetic acid, excreted from sweat and urine and moldy odor, or rodent odor. 3. Ketoacidosis: It may be due to the lack of insulin secretion, resulting in high blood glucose, electrolyte disorders, leading to ketoacidosis, the urine can be rotten apple flavor. 4. organophosphorus poisoning: if the patient accidentally eat organophosphorus pesticide sprayed food poisoning, there may be a relatively large urine odor, urine can be odor. There are many reasons for the heavy odor of urine, and patients should seek medical attention in time.