The body of the lined butterfly valve is a split combination. Easy to assemble and seal adjustment, the valve is in contact with the medium only when the perfluoroplastic seat and the fluoroplastic-lined butterfly plate are in contact with the medium. The inner surface of the valve body channel is smooth, the fluid resistance is small, the CV value is high, the flow capacity is strong, the torque is moderate, and the zero leakage of the medium is completely achieved.