To save expenditure necessary for the measurement register processing of an unregistered land to attain impartial taxation by rapidly and reliably performing the processing.

A national land survey drawing to be the base of taxation, and a current state drawing which indicates the present situation of the actual land are inputted to a map data input part in a newly devised measurement arithmetic instrument concerning a region to be measured. A conformity drawing is outputted by referring to practical data. Then on-site measurement is performed once based on the conformity drawing to provide a boundary stake, and, then, the register processing is performed. Map data may be rapidly and easily inputted by using a digital camera.