PURPOSE: To speedily decide propriety with setting reference by comparing an element becoming an editing object with an element which is previously arranged.

CONSTITUTION: A system is the check system of design reference consisting of an external storage device 4 storing all data on wired patterns, an internal storage device 2 storing the wired patterns in a range which is to be displayed, a central processing unit 1 comparing a pattern interval between data on the wired pattern and data on the wiring pattern becoming the editing object and deciding propriety with setting reference and a display device 3 displaying the wired pattern and the wiring pattern of the editing object. Only data on the wired pattern near the wiring pattern of the editing object is stored in the internal storage device, and the wired pattern stored in the internal storage device is fetched. The interval with the wiring pattern of the editing object is obtained, is compared with a design reference value and propriety is decided.