Like many emerging economies in the Global South, China is experiencing major transformations of its national and local food system characterized by the rise of supermarkets. There has been an ongoing debate on the relationship between the supermarket and the wet market in developing countries. Drawing on data from a city-wide supermarket mapping and surveys conducted in Nanjing in 2019, this paper revisits China’s “supermarketization” process and challenges the prediction of supermarket domination. It reveals that Nanjing’s food retailing system has been shaped by the complementarity and co-evolution of the wet market and the supermarket with great policy support. It is necessary for policymakers to recognize the possibility of the co-evolution of the supermarket and the wet market in other cities of the Global South. This paper underscores the importance of understanding the complex role of the food system in food security.