Female urinary catheterization involves a four-step process of disinfection, catheter placement, saline injection and drainage tube connection, and must be performed by a healthcare professional. Urethral catheterization is referred to as catheterization, usually requires the female patient to lie flat on the bed, the operator is located on the right side of the patient and wearing sterile gloves, after routine local skin disinfection and laying a sterile towel, find the external urethral orifice, and then use a double-lumen balloon catheter slowly inserted. After the catheter enters the bladder, urine can be seen flowing out through the catheter, and then the catheter continues to be inserted partially (usually 7~10 cm), and about 5~10 ml of saline is injected into the balloon to prevent the catheter from coming out. Finally, the catheter is gently pulled outward by 1~2 centimeters, and the drainage tube is connected, and the whole process is finished. Female urinary catheterization process is a more professional process, which must be operated by trained healthcare professionals, and patients or family members must not operate on their own to avoid danger.