PURPOSE: To prevent trouble which is caused by a wiring pattern by securing and arranging a wiring area around a component in accordance with component characteristic information on the number of used pins of each component.

CONSTITUTION: A rectangle which includes the outer shape of an actual component and has the smallest surface area is found as an approximate value of the component outer shape as to all components to be arranged (101) and all components are arranged so as to be close to each other (102). A free area is found from the sum of the area of the arranged components and the area of a substrate (103) and it is judged from the area of the free area whether or not a wiring area can be defined around the components for rearrangement, when there is not the free space, the process is ended. When there is the free area, the wiring area around each component is found from the characteristic information on the component, e.g. the number of used pins and the free area and the allocated wiring area is stored as an enlarged figure of the rectangle found as the approximate value of the component outer shape (104). Then the components are rearranged on the printed board in accordance with the outward shape of the respective reset components.