The process of urinary catheterization under general anesthesia is general anesthesia, airway management, perineal disinfection, toweling, intubation, and fixation. For longer general anesthesia procedures, a urinary catheter is usually required. Urethral catheterization is medically known as catheterization, which is slightly different for men and women, but the basic steps are sterilizing, inserting and fixing the catheter. Male catheterization process is as follows: first clean the vulva, disinfect the penis, urethra, glans, etc.; then disinfect the vulva again, lay out a sterile towel, only the penis is exposed; then insert the catheter, lubricate the catheter with paraffin oil and then gently insert it into the urethra, and then release the clamping forceps, and adjust the position of the catheter and fix it after the urine flows out. The process of inserting catheter for women is similar to that for men, firstly, wash the vulva, disinfect the pubic mound, labia and urethral opening; then wear gloves, disinfect the vulva and spread the towel; then insert the catheter, lubricate the catheter, separate the labia minora with one hand, and then gently send the catheter into the urethra with the other hand and then fix the catheter after the urine flows out. In summary, if there are doubts about general anesthesia insertion of urinary catheter, you should communicate with the surgeon in time.