The most common cause of urinary tract infections in five-year-old boys is caused by a long foreskin or prepuce, and is also seen in the repeated use of the hands to scratch the external genitalia and lead to infection, it is recommended to go to the hospital for further examination to clarify. If there is a circumcision, the prepuce may be local residual more foreskin scale, long time chronic stimulation can produce urinary tract infection, there will be localized redness and swelling of the external genitalia, and accompanied by pain during urination or resistance to urination and other manifestations, the need for further urinalysis, diagnosis and early use of antimicrobials treatment. Can also be seen in the hands to grasp the external genitalia, sometimes not wash their hands, hands have more bacteria repeatedly to grasp the external genitalia, resulting in localized infection of the foreskin caused by urinary tract infections, pain during urination or external genitalia red, swollen, ulcerated, pus and other manifestations of the need to carry out anti-infective treatment, and at the same time, parents should instruct children to wash their hands diligently to avoid using their hands to grasp the external genitalia repeatedly.