In this butterfly valve (10) provided with: a main body (11); valve shafts (13, 14); and a valve body (30) that is rotatable with respect to the main body, the valve body is formed integrally from a core material (32) and a contour forming member (31) that is formed from a synthetic resin material and that encircles the core material and forms the contour of the valve body. The valve body has bearing holes (33, 34) that support the valve shafts, the contour forming member has a bearing inner peripheral part (36) that forms at least a part of the inner peripheral surface of each of the bearing holes, the contour forming member is formed continuously with the bearing inner peripheral part, and the core material has a bearing reinforcing part (35) that supports the bearing inner peripheral part of the contour forming member, radially outside from the rotation axis of the valve body.