When prostate enlargement, the process of catheterization includes steps such as preparation, disinfection, insertion, fixation and marking. 1. Preparation: ① Self-preparation: wear mask, hat, hand disinfection; ② Preparation of goods: prepare catheterization kit, disinfectant, etc.; ③ Patient preparation: take the supine bent knee position. 2. Disinfection: Expose the urethra and disinfect it with disinfectant from outside to inside. 3. Intubation: lubricate the catheter and insert it slowly into the bladder along the urethral orifice. Before insertion, the patient should be informed and instructed to take a deep breath to cooperate. Pay attention to the process of catheterization to move gently. 4. Fixation and marking: After the urine is drawn out, inject 10~15 ml of sterile solution into the catheter, pull and fix it, mark it well and record the time. In addition, attention should also be paid to regular replacement of the drainage bag during the use of the urethra, pay attention to the disinfection of the urethral opening to maintain local hygiene. When patients with prostatic hyperplasia have urinary retention, they can choose to use catheter drainage, if necessary, please go to the hospital, operated by specialists, do not use on their own.