Triple offset metal to metal butterfly valve is widely used in more severe applications(such as high temperature,medium with hard particles and shut off,etc.) Triple offset metal to metal butterfly valve can be bi-direction shut off. Its oval sealing area on the disc only contacts the valve seat in the closed position, which greatly eliminates the friction between the disc and the seat, and increases the service life of the disc and the seat. When close the valve, the oval sealing ring on disc has uniform compression deformation contacting with the seat, so as to achieve a long-time reliable bi-direction zero leakage.