Japanese flood control was rapidly developed in Modern Ages when regular flood protection works began onnationwide scale. It is flood prevention cooperatives that promoted those public works by bearing a part of the expenses in Modern ages.Flood prevention cooperatives are classified into 3 types according to functions. They are the one that takes a share in the expenses of flood protection works and irrigation-drainage works (type I), the one that practices flood defense activities (type II), and the one that petitions to realize and promote river improvement works and acts a part of the works as an agent of prefecture (type III). The author conducted research on cooperative dues that support activities of cooperatives. The results are as follows.Amount of share in the expenses taken by flood prevention cooperatives much differs in compliance with their functions. In type I cooperative dues were very high, in type II they were less and in type la they were much less. In all types cooperative dues were imposed by standards that based on the degree of flood damages. Especially in type I, much amount of cooperative dues were levied according to many grades, but type II and type III had a few grades. Their objects of imposition were land and houses, and in urban areas they included fabrics such as railroads.Flood prevention cooperatives dissolve when they accomplished their purposes in each function. But the cooperatives of type II shift to public flood defense corporations that consist of municipalities and act by budgets of municipalities.Flood prevention cooperatives fully understood natural features of geomorphology, hydrology and so on, and social features of land use, land ownership, and so on of their areas. On the basis of these recognition they contrived their unique imposition system in consideration of benefit by public flood prevention works. In consequence they promoted public flood prevention works by taking a share in expenses.