In this paper, the writer shows the urban growth of Muroran and the neighbouring two cities, and analyzes some factors and effects of the urban growth. The results obtained are as follows:
1) Built-up area was developed over the Etomo Peninsula till the end of World War II. After the war its expansion has been seen in the eastern part (Rantô district) of Muroran.
2) Urban growth extents to the two neighbouring cities, Noboribetsu and Date, since 1965.
3) There are three main factors in urban growth of Muroran; the first is the enlargement of manufacturing industries, the second is the construction of public residences and the third is the fear of industrial pollution in the central part of the city.
4) According to the urban growth, the center of population distribution moved from the western part to the eastern part of Muroran, and according to the change some urban facilities have been moved to the east, so that the Ranto district seems to become a new C. B. D. in Muroran before long.
