Urine has a foul odor, may be a physiological phenomenon, may also be caused by disease. 1. physiological phenomenon: normal fresh urine, there will be a faint smell, if eating too greasy food, body sweating, urination, or vomiting, diarrhea, resulting in the loss of body fluids, resulting in the concentration of urine, may cause urine smell. 2. Diseases caused by: for example, diabetic ketoacidosis, will cause urine with rotten apple flavor; urinary tract infections may cause urine with ammonia odor; organophosphorus poisoning may appear urine with garlic flavor; vesicorectal fistula may appear fecal odor. Urine odor is recommended to go to the hospital in time to check, if there is a disease caused by the need for active treatment.