Abstract: In the rapid urbanization process of China, urbanized land expands quickly at the same pace as urbanized population grows. Recent researches have been focused on land urbanization which considers the urbanization of land in current China as a reckless rash which is incompatibly faster than the urbanization of population and moreover, results in understandable inefficiency. To clarify the definition, the implication and the measurement of land urbanization, the authors have reviewed related literatures on urban expansion, urban sprawl, land use conversion, especially those in China; analyzed the reality and background of urbanization of land under the rural-urban dual land system in China; then developed the definition of land urbanization as the transition of land to construction land with urban attributes. The definition includes not only the commonly agreed transition of rural farmland to urban construction land, but also the transition of rural construction land to urban construction land, and the latter has been found to be increasingly significant for efficient land use. The definition describes the unique dual process under the dual land system more accurately and is measurably consistent with the implication of population urbanization in the similar dual population management system in China. Furthermore, the authors proposed the measurement of land urbanization as the ratio between urban construction land and the summation of rural and urban construction land, namely the so-called“rural-urban construction land”. Based on this proposal, further researches could be conducted on the comparison between land and population changes in urbanization process, and other elements such as economic and social factors and transition of land use efficiency.

Key words: land urbanization, land urbanization rate, land use conversion, urban expansion