An object of the present invention is to provide wiring board design system and wiring board design method to determine a component and a wiring pattern in real-time when designing a wiring on a circuit board. The wiring board design system provides a cloud service for a terminal which is used by users via a network. When to arrange components on the circuit board, while pushing out automatically wirings which are overlapped with the components on the arranging position, the wiring board design system secures a space on that can arrange the component. The wiring processing is performed automatically and the fine adjustment such as rotation, movement of arranged components is performed automatically if necessary. The processing for equalization is performed so as to be the equal wiring density on the circuit board.