PURPOSE: To precisely decide the form of chip parts and the quality of a mounting direction as to the chip parts which are surface-loaded on a wiring board by means of solder.

CONSTITUTION: The positions of the corners of contourines in the chip parts are decided based on three-dimensional form data in the surface-loaded chip parts 1 (steps 102 and 103). A primary regression operation is executed based on the coordinates of plural points on a side where solder 2 is not given among respective sides in adjacent corners at the contour lines, and the inclination angle θ of the side is obtained (step 104). The quality of the loading direction is decided based on the obtained inclination angle θ (step 110).