<p>The booming development of China’s O2O (Online to Offline) e-commerce has attracted intense academic discussion. However, studies on the spatial evolution of O2O e-commerce are rare. Therefore, this study adopted methods such as spatial statistics and geodetector to explore the spatial evolution and determinants of O2O e-commerce. The main conclusions are as follows: (1) China’s O2O e-commerce development has distinct stages: 2012–2014 witnessed a period of rapid growth, during which O2O e-commerce completed swift spatial expansion between cities; 2015–2016 marked a phase of unprecedented expansion, with O2O e-commerce rapidly undergoing spatial diffusion within cities; and 2017–2019 represented a steady development period, during which the O2O e-commerce market pattern has essentially been determined and entered a trajectory of normal development. (2) The overall spatial pattern of O2O e-commerce development has broken the law of China’s economy decreasing from southeast to northwest to a certain extent. Instead, there has been a noticeable rise in central and western core cities, rapidly catching up with eastern coastal cities, resulting in a “multipolar” situation. (3) The spatial expansion of China’s O2O e-commerce exhibits distinct characteristics of mixed diffusion, with early hierarchical diffusion and later contagious diffusion. (4) There has been an increasingly significant polarization phenomenon in the evolution of China’s O2O e-commerce. (5) China’s O2O e-commerce development is influenced primarily by factors such as urban population, traditional commerce, economic scale, informatization level, and transportation. Moreover, the impact of each factor continues to increase with increasing O2O e-commerce development level.</p>