To carry out evaluation of a road surface property easily and in a short period of time without being costly. Measurement data of a road surface measured for a predetermined road width along a path of a road to be measured is acquired; a unit area having a preset length dimension along the path in the road width is set along the path; a model plane in the unit area is set based on the measurement data at each point in the unit area; point group data is generated from a spaced amount of the model plane and each point in the unit area, visualize and display the spaced amount in the path, and display a result of evaluation obtained through statistical processing with the path shown on a map.