Provided is a lined butterfly valve that is corrosion resistant to fluids, that simultaneously improves top and bottom sealing properties and shaft sealing properties so as to reliably prevent leaks, and that is capable of maintaining said sealing properties even if a disc moves to the secondary side due to fluid pressure. A disc (12), which is covered by a lining (32), is provided inside a cylindrical body (11) covered by a seat liner (20) and is able to open and close via a stem (13). The expansion of the diameter of a shaft sealing portion (18) of the stem (13) is prevented by sandwiching said shaft sealing portion (18) between a ring body (22) and the stem (13); and the sealing properties of top and bottom seal portions (19) are maintained as a result of the seat liner (20), which is positioned at top and bottom boss surfaces (37) of the disc (12), being pressed via the ring body (22) due to the spring force of a spring (44) provided inside a shaft installation part (27) of the body (11).