The article deals with the experience of creating airports on artificial islands in Japan. On the basis of ministerial and departmental statistics, available on the Statistics Bureau of Japan portal and on the websites of regional services of individual prefectures, the role of these airports in solving the country’s transport problems is considered. A definition of a maritime airport has been formulated and their share in the total number of airports, passenger and cargo turnover of all airports in the country has been determined. The peculiarities of seaports localization are revealed. The main phases of Kansai airport construction and the “three airport problem in the Kansai region” are considered.