Land readjustment is a tool for land assembly so as to provide buildable land and infrastructures for urban development. After land readjustment, it is supposed that lots of land will be supplied to the land market, and this might lead to mitigate the shortage of land supply and speed urban development in peri-urban area. However, most pieces of land are returned to landowners, who decide to supply the land or not. In this paper, if landowners either sell or develop their land after land readjustment immediately is going to be examined. Moreover, how land readjustment affects the land price will be analyzed as well. The case of Tucheng land readjustment project in New Taipei City will be studied for answering these two questions.