This paper describes progress of the cooperation as to the integration of EC market and the change of industrial structure. For the structural change in the industry and economy accompanied by the integration of EC, effects of the Maastricht Treaty on the economic structure of EC are described. It is considered that the EC countries are affected by the political and economical restrictions due to the agreement of this treaty. For the change in the distribution structure accompanied by the integration of EC, obstruction factors of the deregulation of EC transportation market are especially investigated. Differences in the distribution capacity, various regulations and standards, and labor condition among individual countries are pointed out as the obstruction factors. For the unity of Germany and its economical and administrative influence, various problems are pointed out as to the economical confusion, progress in the de-nationalization of enterprises, management of real estate and land, etc. For the structural change in the road freight market in the member nations of EC, the structure of road freight market is made clear for the previous West Germany before the integration of European market. It is confirmed that the internationalization of the German domestic market is being promoted.