A feature analysis apparatus which enables visual confirmation of features of an inspected object and which enables limitations on the degree of freedom of classification based on the features to made relatively smaller is provided. It acquires inspected object information of an inspected object (S1), analyzes the inspection information to determine values of feature parameters of each of the plurality of layers (S2 to S5), uses values of the plurality of feature parameters and their corresponding directions for each of the plurality of layers to generate a single parameter vector (S2 to S5), converts the parameter vector to a layer vector which is a 3D vector in a predetermined (S2 to S5), and couples the plurality of layer vectors obtained for the plurality of layers in the order of the layers and generates a set of coordinate values of the plurality of nodes obtained in the 3D space as feature information of the inspected object (S6).