In Aichi Prefecture, there are 15 cities and a ward which make up the automobile industrial agglomeration. Toyota City is functioning as not only a hub of Aichi type agglomeration but also all in Japan to some extent. Exceptionally considerable car plants in Toyota City showed steady growth after 1990's. The manufacturing industry of Toyota City is in the condition which therefore may be said as the car mono-culture. The population growth of Toyota City was decided by demand of car plant laborer before 1990's. The amount of the municipal taxes storage and the citizen strength a person of Toyota City greatly depend on the management achievement of the Toyota group. In this paper, the problem whether and how the auto sector of Toyota City developed other manufacturing sectors is not clarified.