As an important channel connecting the ocean and land, the internal and external of the region, the importance of the Bay in the development of the modern world is beyond doubt. At present, it is more and more obvious that the development center of the global economy is shifting to harbor cities. 50% of the world economy is concentrated in the coastal and riverside areas 150 km² away from the coastline. For example, in the process of global economic transfer to Asia, it has led to the rapid development of Northeast Asia, Southeast Asia, South Asia and other regions. Northeast Asia has formed the harbor group with the port of Korea Busan, Qingdao port of China, Yokohama port of Japan and Kobe port. Southeast Asia is centered on the city of Hongkong and Singapore. In addition, the developed regions in Europe with strong traditional maritime transportation mainly take Rotterdam, London and Hamburg as the centers, while the United States has formed a rapid economic development region centered on New York and San Francisco. At the same time, with the opening and active of global economy, especially the promotion effect of harbor on harbor cities and countries is becoming more and more obvious. Basically speaking, harbor is one of the basic conditions for the formation of modern society. The original harbor is small in scale and plays an insignificant role only as a supplement to urban land transportation. The backwardness of science and technology and economy makes the economic and trade activities less frequent, and the operation of the harbor is only supported by the city's population flow and a small amount of trade and transportation activities. At this stage, the value of the harbor itself is low, and it mainly depends on the resources of the city. But later, thanks to the progress of science and technology, the mode of transportation has also been greatly improved. The convenient transportation network covers the city and its surrounding areas on one side, and expands to the ocean on the other. Therefore, the harbor gradually began to be valued by the city or regional rulers, and provided a large number of resources for scale expansion, in order to achieve the purpose of opening up the ocean boundary and the world market. At this time, the harbor began to rapidly promote the economic and trade development of the harbor city. The frequent floating population brought about by the port transit function activated the industrial vitality of the city, attracted a large number of industries such as commerce, industry, finance, handicraft industry, manufacturing industry, etc., which greatly enriched the diversification of the city's industrial functions, also made the city's population continue to increase, promoting the city's industrial vitality The port transit cities will develop into regional or international comprehensive central cities. In modern times, the development of the world market and the formation of the global trade network make the status of the harbor further improved, which has become one of the most important factors affecting the development of the harbor city. The relationship and influence between harbors has gradually become a hot topic in modern harbor research.
First of all, there is no doubt about the relationship between the harbor and the harbor city, because the initial development of the harbor is based on the resources provided by the harbor city. However, in the later development process, because the development of the harbor promoted the growth pole effect, and the city's control over the harbor weakened, the two began to separate. And because of the contradiction between harbor expansion and urban development, there is a fundamental conflict between harbor development plan and urban development plan to a certain extent. Therefore, from the perspective of the development process of the harbor, the influence and connection between the harbor and the harbor city is not continuous, stable, synchronous and positive, but changes with the strength of the two. In the period of intense contradictions and conflicts, if we can not find and adjust the change of the relationship between the two and adjust the plan, it is easy to intensify the disharmony, which will have a negative impact on the positive development of the harbor and the harbor city. The research on the relationship between harbors and harbor cities is necessary for all harbors. The main objects of this study are Chinese ports and Korean Ports, which are representative harbors in Northeast Asia. Since the 1990s, the center of world economy has been shifting to Asia, especially to the East and northeast of Asia. Therefore, in Northeast Asia, the competition of world shipping center and hub harbor is becoming increasingly fierce. At the same time, the competition of Northeast Asian ports also presents a new pattern in the change of global economic situation. The most prominent performance is the decline of Kobe port and Yokohama port, and the rise of Korean ports and Chinese ports. Therefore, this study starts from the relationship between the harbor and the city, takes Korean ports and Chinese ports as the research objects, analyzes the samples by the way of statistical data, and tries to understand the basic development of the harbor and the influence degree of the specific harbor elements on the harbor city through the interaction coefficient between the harbor elements and the harbor city elements, puts forward reasonable suggestions on the harbor development plan from the perspective of mutual promotion of port and city, so as to promote their common development under the premise of harmonious development of harbor and harbor city.