A laminated plate includes first and second plates bonded to each other via an intermediate layer. The laminated plate includes a first main surface of the first plate opposite to the intermediate layer; a second main surface of the first plate and a third main surface being in contact with the intermediate layer; a fourth main surface of the second plate opposite to the intermediate layer. A thickness of the first plate is thicker than a thickness of the second plate. In a planar view, the laminated plate includes a peripheral region and an in-plane region. In a cross section orthogonal to an outer periphery of the laminated plate, a distance from an outermost periphery of the second plate to the first plate in a thickness direction with respect to the outermost periphery is three times or less a distance between the first and second plates in the in-plane region.