PROBLEM TO BE SOLVED: To provide a surface shape evaluation method and device of a saw wire capable of evaluating the surface shape of the saw wire accurately, efficiently, and quantitatively.SOLUTION: The surface shape evaluation device of a saw wire includes: an edge processing unit 10 that axially divides a photographic image related to the saw wire surface on which an abrasive grain adheres into a plurality of regions, and colors a part corresponding to the edge of the abrasive grain by coloring processing of a low-luminosity pixel and a high-luminosity pixel on the basis of the average value of the luminosity in each divided region; an extraction processing unit 11 for drawing a circumscribing circle circumscribing the colored region having undergone the coloring processing so as to surround the colored region and extracting an abrasive grain part; and an evaluation processing unit 12 for evaluating the surface shape on the basis of the area and center position of the drawn circumscribing circle.
