Abstract: The molten steel corrosion and ultrasonic vibration resistance of a corundum stick, a tungsten alloy stick, a metal Mo stick coated with ZrO₂ outside, and a Mo-Al₂O₃-ZrO₂ ceramic metal tube were investigated for ultrasonic treatment of molten steel. The results show that the corundum stick can endure high-temperature molten steel corrosion, but ultrasonic vibration caused it fracture. The tungsten alloy stick could endure huge ultrasonic vibration but end fusion will take place within a short time during the ultrasonic treatment process of molten steel. The metal Mo stick coated with ZrO₂ outside had corrosion resistance ability in molten steel during a short time (1-2 min), however, low ability to withstand strong ultrasonic vibration. The ceramic metal tube had the ability to endure not only strong ultrasonic vibration (250 W) but also high-temperature molten steel corrosion, so it could be served as the probe for ultrasonic treatment of molten corrosion.