Pressure sore is an indicator of nursing quality. Nursing intervention investment affects the prevention result of pressure sore. The pressure sore of ear due to wearing the oxygen mask not only causes the patient extra medical injury, but also wastes the medical cost unable to estimate in the future. This project used the sheath to protect the ear in order to reduce the pressure sore incidence rate and increase the patient's comfort, but also enhance the satisfaction of the caregivers and nurses. This project is worth popularizing in the furture.