PURPOSE: To raise a designing efficiency by selecting a device having a wiring accuracy to avoid a disconnection, a contact between wirings even under wrong conditions in which an error occurs in the wiring by a wiring device in manufacturing steps and enhancing the quality of a designed wiring diagram between an IC chip and a frame.

CONSTITUTION: A wiring diagram forming unit 4 forms a wiring diagram in which chip drawing data and frame drawing data combined by a data mixer 3. An error data forming unit 9 reads a wiring accuracy of a wiring device, set to an adaptive device setter 8 as a device adapted for a wiring operation and forms wiring data when an error occurs in the wiring device. A rule checking unit 5 checks whether wiring data when the error occurs satisfies a wiring rule or not, and an adaptive device detector 10 detects the wiring device which has passed the check.