Regional disparity has become a major problem in both China and Japan. Governments are emphasizing developing rural areas (Japan: depopulation region) to decrease the economic gap they have with major urban centers. This paper compares two successful cases in each country and identifies a sustainable development approach to establishing local autonomy to develop business and/or industry. The factors of success in these two cases were analyzed, and some implications and insights were clarified. Local specialties should be taken into account, and adopting a suitable strategy and establishing autonomy for the local people is a realistic and effective approach to developing the socio-economy of regional areas and to narrowing the disparity. During this development, a wise leader or a team of leaders is essential, and this leader (s) also must have open communication with the local community.