Due to the advantages of relatively mature technologies and low greenhouse gas pollution, wind energy represents a vital energy alternative for electricity generation. Using onshore wind power has become increasingly important in China. Currently, wind energy faces energy return on investment (EROI) and geographical constraints, which both have significant impacts on net wind energy potential. This study combines GIS modeling, wind turbine performance, and the wind speed distribution with a large daily dataset to estimate onshore technical and net wind energy potential in China and to visualize the available wind energy potential. In this study, more detailed local topographic effects (changing air density, surface roughness, air density, array placement efficiency) were considered despite the complexity of applying them at a country level. The results show that the technical potential of China’s onshore wind energy could reach 2560 TW h/yr in a 0% agriculture land scenario and 3501 TW h/yr in a 70% agriculture land scenario, and the net energy potential could reach 2335 TW h/yr and 3194 TW h/yr when EROI = 11.4:1 (when averaging performance of turbines across geographic areas) in these two different scenarios.