To provide a process of producing a disk of a three-piece type aluminum wheel for two-wheeler which has a shape desired by a customer and can secure the safety.

In the process of producing a disk of a three-piece type aluminum wheel for two-wheeler, a shape desired by a customer is converted from the data of a two-dimensional drawing into the three-dimensional CAD data under the computer control in the production of a disk of a three-piece type aluminum wheel for two-wheeler, the mechanical characteristics are obtained from the CAD data, and compared with the prepared safety standard. If the safety standard is satisfied, the mechanical characteristics are defined as the CAD data. Otherwise, the shape is changed to an adequate one to satisfy the safety standard, and the mechanical characteristics are defined as the CAD data.