According to an embodiment of the present invention, a method of measuring a surface of an object having a curved shape by measuring a distance from a measurement head to the object, includes: setting a measuring region of the object and a threshold value of concave and convex; acquiring shape reference data including the curved shape of the object; acquiring three-dimensional data of the surface of the object by measuring the distance between the object in the measuring region and the measurement head; acquiring curve removed data by removing the shape reference data from the three-dimensional data; calculating second reference data by calculating first reference data based on the curve removed data, by removing data exceeding the threshold value with respect to the first reference data, from the curve removed data, and by averaging the curve removed data; and calculating shape data of the concave and convex.