This paper creates a new conception to construct the international central city of the Tumen River Development Zone on the basis of the analysis of the superiorities and problems for developing cities from the view of present condition in the Tumen River delta area and the background of Northeast Asia. The united and polycentric international city is the best distribution model not only in the spatial structrue but also in the organizing form. Its rationalization and practicability is thoroughly proved from varous aspects including the urban planning principle; comparison of port cities; specific characteristics of this area cooperation; and natural, environmental, social, cultrual factors etc.