A clutch apparatus is equipped with two clutch structures having a clutch drum therein. A driven plate and a piston are provided in the clutch drum of each clutch structure, and a primary coned disc spring and a secondary coned disc spring, which are ring-shaped, are provided between the driven plate and the piston. A flat portion is formed on an inner peripheral portion of a convex surface of the primary coned disc spring, and the flat portion can come into contact with a counter member first when a load is applied. A load in a flat condition due to elastic deformation is adjusted by the flat portion so as to be a desirable value. Blanks and of the primary coned disc spring and the secondary coned disc spring can be obtained from one sheet of material having the same thickness. In this case, the flat portion is formed by press forming on an inner peripheral portion of the blank in view of the shape thereof after bending forming is performed.