Modern newspapers, introduced into Japan in the 1870's, have diffused as one of the modern cultural elements throughout the country. From the human geographical aspect of modern newspapers, some geographers have remarked on the interaction between the newspaper system of publication places and circulation areas, and the central place system (Dickinson, R. E., 1947; Blotevogel, H. H., 1984 etc.). On the supposition that their ideas are also valid in the Japanese case, we can clarify the reformation process of modern spatial organization in Japan using the newspaper business as an indicator. This paper is composed of two sections. In the first section, the locational development process of newspaper publication is analyzed by comparison with the development process of the Japanese urban system. We examine the changing process of newspaper circulation spatial structure in the second section. In this case, our attention is directed to the core-periphery problem in newspaper circulation.The following results were obtained in this inquiry:First, we can find that there was a downward diffusional process of newspaper companies from the prefectural seats to the local centers. The concentration of political and economic functions and population had caused the prior location of newspaper companies in the prefectural seats. Until the 1930's, the number of newspapers had increased and publication places had diffused to the lower ranking centers. However, the distributional pattern wasn't uniform. Newspaper publication was concentrated in the Tokaido and Sanyodo regions, Nagano Prefecture, and Niigata Prefecture. On the prefectural scale, most of the newspapers were published at the prefectural seats. On a national scale, the capital of Japan, Tokyo, was the largest center of newspaper concentration. These situations at prefectural and national scales are explained by the importance of political functions concerning the location of newspapers. On the other hand, local community papers developed in some regions, for example in Nagano Prefecture. These contributed to the diffusion of newspapers in the lowest-class regions. However, in the 1940's many companies were integrated at the prefectural level under a national policy. So, the prefectural seats formed a monopoly of newspaper publication within each prefecture.Second, there are some findings as to the sales wars between metropolitan newspapers and local papers in the regional markets. The metropolitan newspapers were established in Osaka or Tokyo and expanded their substantial circulation area to peripheral regions with the times. The share of metropolitan papers had been relatively high in regional markets at the time when newspapers were first introduced into Japan. However, the growth of local papers supported by local political parties gave the dominant position to the local papers in many prefectures. Some metropolitan papers had been circulated at provincial or sub-national scale since the 1890's. The frontiers of metropolitan papers advanced along the railway routes extending from Tokyo toward peripheral regions. But the share of these papers was dominant merely in the neighborhood area of publication place. From 1900 to the 1910's, these papers gained the priorities of market share in the Kanto Region or Kinki Region. It was in about 1940 that the national newspapers appeared with regard to their share in the regional markets. The formation of“national newspapers”implies the cultural centralization of Japan. However in the national newspaper integration process, “provincial”papers, which had priority of share in the provincial regions beyond their prefecture of publication, had grown in two regional metropolitan cities: Nagoya and Fukuoka. Nagoya and Fukuoka became secondary centers of newspaper publication. The provincial papers formed cultural subregions in the modern spatial organization process.