Different from Taipei City and Kaohsiung City, the degree of urbanization of Taichung Metropolitan Area did not speed up until 1970s. Due to the pressure of urban population growth, suburban counties become the first areas shouldering urban population pressure. The characteristics of suburban population accompanying urban development are getting more and more obvious. The most obvious evidence is land use transformation of suburban county.
According to urbanization characteristics of Taichung City, time span of this research is divided into two stages: (1) urbanization of Taichung City and low suburbanization (1982-1988) (2)Suburbanization of Taichung Metropolitan Area (1988-1994). Using Taya County as a case to investigate how land use has been transferred by way of Cluster Analysis applying homogeneities of land use transformation. In order to comprehend land use transformation of Taya County and the relationship with urbanization of Taichung City, this study uses population documents to display suburban characteristics of Taya County. This study has shown that land use transformation of Taya County is influenced by the core of Taichung Metropolitan Area. The demand for urban development is the top priority for land use transformation. The variability of land use has been in accordance with the urban development. It is clear that the degree of land use transformation of Taya County is declining outwards along "Taichung – Taya – Fenyuan" axis.
It can be concluded that land use transformation of Taya County is deeply influenced by urbanization of Taichung City. With urban sprawl of Taichung city, suburban counties become the top choices for urban development. Moreover, urban influence invades suburban counties along the roads connecting the core area and the sub-core areas, as a consequence, land use of suburban counties has been transferred to meet urbanization needs of the core area.
