Making a plan of city planning roads network in Tokyo was started in 1945 under the coordination of Mr. Ishikawa, director of Section of City Planning, Tokyo Metropolitan Government (T. M. G.). And this Master Plan was determinated by Council of City Planning in Tokyo Region on March 1946. In this Plan, Mr. Ishikawa applied for 100-m wide roads. But for the worst financial condition of Japan, the American famous economist and mission recommended to improve the economic policy of Japan, especially the reform of the Japanese taxation system. Japanese Government accepted the recommendation and executed new economic policy. Moreover the Government requested T. M. G. reconcideration of city planning roads. According to the request, Council of City Planning in Tokyo Region determinated the new narrower roads network plan on January 1950. In this plan, the width of 100-m wide roads was reduced.