To provide a method for measuring even a nonspherical surface shape of a lens by setting an origin of measurement accurately.

An initial origin is set in initial origin setting step and a (z) coordinate value is measured for a coordinate value perpendicular a measuring direction on a coordinate plane intersecting the measuring direction perpendicularly in the vicinity of the vertex of a lens 3 to be measured with reference to the initial origin in coordinate value measuring step. Optimal parameters x0, z0, c, k, e4, e6,... are then estimated based on the (z) coordinate value according to a model formula in estimation step. Subsequently, a measurement origin 1a is set through translation of the initial origin using the optimal parameters x0, z0, c, k, e4, e6 in measurement origin setting step. Finally, cross-sectional shape of the lens 3 is measured accurately including the vertex thereof with reference to the measurement origin 1a in measuring step even for a nonspherical shape.