A blade structure of a torque converter, having a plurality of blades, is produced according to processes. The processes has (a) stamping a plane plate into a first shape, the first shape has (i) the plurality of circumferentially arranged blades, (ii) ring-shaped first connecting portions, each of which integrally couples the adjacent blades together at an outer circumference side of the blade structure, and (iii) ring-shaped second connecting portions, each of which integrally couples the adjacent blades together at an inner circumference side of the blade structure, (b) curving a surface of the stamped blade, (c) inclining the blade at a predetermined angle with respect to the first and second connecting portions while inclining the first and second connecting portions, and (d) adjusting a distance between the adjacent blades and shrinking the first shape in a radial direction by the inclination of the first and second connecting portions.