The objective of this study is to describe the influence of railway and railway station on the change of city structure in Korea in the early 20th century. In the 1900s, railway was constructed in Japanese concessions and in new pore cities such as Incheon, Busan, and Wonsan. In the 1920s, railroad construction became related with the cities, which could produce the corps. In the 1930s, railroad also became related to the colonial industrial cities. Traditional city structure was then completely changed because new city structure was focused on not Seoul but Japan or harbors towards Japan. So Korean cities, which were netted by railway, had become the subsystem of Japan in the early 20th century. Korean cities have developed on the basis of this system until 1945. For example, the twelve main cities were chosen through the relationship with Japanese life, and the provincial office governments moved near railroad stations. However nowadays, these cities have possibilities of being international cities, such as Incheon and Busan, because of the extroversion of these cities.