The present invention is: a pattern measurement device that, regardless of increased fineness, deviation, or the like of a pattern, accurately and stably performs measurement on the basis of edge identification or pattern or edge judgment; and a computer program. The pattern measurement device classifies pattern sites (G1, G2, G3, G4), which are repeatedly arrayed at a specific interval, in accordance with the position of the pattern sites, and executes a pattern edge type identification, a pattern type identification, or a measurement of the dimensions between predetermined pattern sites on the basis of an association between the classified pattern sites and information pertaining to the pattern edge type or information pertaining to the pattern type. The computer program causes a computer to execute the abovementioned process.