The standard operation specification of urinary catheterization can generally be divided into disinfection, intubation, fixation and other steps to be carried out. 1. Disinfection: first of all, let the patient take a comfortable supine position, avoid mental tension, use iodophor to disinfect the external genitalia, as well as the urethral orifice repeatedly after laying on the sterile hole towel, and then disinfect the genitals to ensure the sterility of the urethral orifice. 2. Insertion: choose the appropriate type of catheter, coated with liquid paraffin, and then straighten the penis from the urethral orifice slowly inserted, see the urine discharge, and then inserted into the 3 ~ 5 cm. 3. Fixation: generally use a syringe to extract 10~15 ml of saline, injected into the water bladder of the urinary catheter and then pull the urinary catheter to ensure that the urinary catheter is not dislodged, after which the hole towel is removed, and the urethral opening is disinfected again to complete the operation. Catheterization should go to the regular hospital standardized treatment, so as not to cause other complications.