In order to inspect a board, a measurement area is set on a board, and reference data and measurement data of the measurement area are acquired. Then, a conversion condition is established for the measurement area, and a conversion relation is acquired according to a distortion degree between reference data and measurement data. Thereafter, validity of the conversion relation is verified by using at least one of verifying that a comparison feature object satisfies the conversion relation, verifying that a verification feature object selected from feature objects satisfies the conversion relation and verifying that a pad formed on the board satisfies the conversion relation. Then, the conversion condition is confirmed, and an inspection area for inspecting a measurement target is set according to the confirmed conversion condition. Thus, an inspection area may be correctly set so that distortion is compensated for.