In recent years, the necessity of the study which evaluates the economic effect of the utilities is rising. The purpose of this study is to make clear from the theoretical and the empirical aspects about the economic effect for the land improvement investment. An analysis is composed of two parts. One is the part which computes a capital stock of the agricultural and and computes the volume of the land improvement investment by the change of the capital stock.  Another is the part which measures the influence which the land improvement investment gives the agricultural
production.