It is an urgent task now to realize urban renovation by both revitalizing economic activities and reconstructing the city into peaceful and safe space. Above all, we need to cope urgently with redevelopment of widely scattered low or less utilized areas in Tokyo and other big cities, as the improvement of these areas into livable environment refers directly to the improvement of residents' living space as well as to desirable preparation for the aged society. Of those low or less utilized areas in CBD, in heavily densed residential areas where ownership are somewhat limited and complicated, it is difficult, in general, to proceed improvement projects, as conservative aged population is prone to be dominant in such areas. In Chuo City, where promotion of more efficient land use is regarded to be necessary especially, many areas are still left yet to be improved. We reckon that reverse mortgage system can effectively be applied as a new method to carry out residential environment improvement projects in densily built up CBD areas. This system can allow aged people etc. to keep on living on present site while developers are required to take enough time to promote redevelopment projects. Majority of the institutionalized reverse mortgage system in Japan so far have been linked with welfare services provided by municipal government, thus its application has been confined to individual utilization of the respective asset. “Town-Building-Type Reverse Mortgage System (tentative naming)” that we propose here not only enables landowners to extract living cost from their owned assets, but also enables them to aggregate small scaled ownership to promote larger scaled land utilization.