In an exposure process or etching process, an image feature amount useful for estimating a cross-sectional shape of a target evaluation pattern, process conditions for the pattern, or device characteristics of the pattern is calculated from an SEM image. The image feature amount is compared with learning data that correlates data preliminarily stored in a database, which data includes cross-sectional shapes of patterns, process conditions for the patterns, or device characteristics of the patterns, to the image feature amount calculated from the SEM image. Thereby, the cross-sectional shape of the target evaluation pattern, the process conditions of the pattern, or the device characteristics of the pattern are nondestructively calculated.