As urbanization goes fast in China, the demand of land resources is far beyond its supply. One of solution is to reform village-in-city, to extensively use land and to increase the land utilization efficiency, in line with governmental policies. This paper, based on a case study on Kunming city, applies the construction land standard per capital and GIS data as indexes to estimate the land-saving potential to reform the village-in-city, with the results that the lands have been increased by 1792.79 hm 2 and 1288.87 hm 2 inside and outside urban planning zones, respectively. This method is of significance to improve the land extensive utilization efficiency.