1. An apparatus for inspecting a three dimensional shape, comprising: electron-beam irradiating means for irradiating a focused electron beam onto a specimen while scanning the electron beam; signal detecting means for detecting secondary electrons generated from the specimen by irradiation of the electron beam; and signal processing means for performing arithmetic processing on the signal from the signal detecting means; wherein the signal processing means has both an evaluating function of dividing the signal waveform obtained by the signal detecting means into plural regions on the basis of variation of the signal quantity and evaluating the three dimensional shape of the specimen using sizes of the divided regions, and a displaying function of preparing maps each representing a distribution in a wafer plane with respect to two or more kinds of shape-representing values selected from a group consisting of a size of the plural divided regions and values obtained by summing or subtracting the sizes of the plurality of the divided regions, and displaying these wafer maps in arrangement or in a switch-selectable manner.