Abstract: To meet the needs of land reform and development, Land Administration Law has added tract development as a new type of expropriation based on public interest. However, there are still some problems in tract development expropriation practice, such as unclear content, insufficient test standards and vague application types of public welfare requirements. The public welfare of tract development expropriation integrates the staged composition in time and the different composition in content, that is, the front-end public welfare is embodied in the supply of public goods, and the back-end public welfare is embodied in the comprehensive utilization of land and a certain proportion of public welfare land aiming at sustainable and win-win development of the tract. Based on the concept of interest measurement, the test standard of public welfare requirements for tract development is whether the ratio of personal interests of property and survival interests to public interests, which are the summation of the aforementioned public interests and the deduction of ecological public interest loss, is far less than 1. And the correlation of specific public welfare, sustainability and necessity of back-end development, utilization efficiency of back-end public welfare land, and whether other ways can solve land-use problem should be considered at the same time. In practice, national and provincial economic and technological, high-tech and industrial development zones as well as large-scale urban village reconstruction can generally be applied to tract development expropriation, while ordinary commercial housing, inefficient land use in urban and rural characteristic town should be excluded.