Detailed discussion on global energy trading structure and topological characteristics is the necessary knowledge for formulating energy trade-related strategies. From the perspective of complex network, this study examined the topological structure and evolutionary characteristics of the global energy trading network, and analyzed the competition and cooperation relationships between the trade groups and supply and demand countries. The results show that: 1) Since the 1990s, global energy trading relations have become increasingly complicated. In recent years, the number of energy trading entities has remained stable, and nearly 80% of the countries/regions in the world are involved in energy trade. 2) The global energy trading network has both "small world" effect and scale-free characteristics. 3) The energy export center has gradually shifted from East Asia, the Middle East, Australia, Europe to Russia, the Middle East, North America, Australia, and West Africa regions. At the same time, the import center has shifted from East Asia, Western Europe, and Australia to North America, East Asia, and Western Europe regions. 4) There are four trade blocs in the global energy trading network, namely, the trade blocs led by the United States, European-Russia countries, East Asia-Southeast Asia countries, and Australia-India-Africa countries. Geographical distances, institutional differences, historical, cultural, and political relations are important reasons for the change of trade blocs. 5) Within the trade blocs, the dependence between core countries is asymmetric. The diversification of import sources of energy demand countries is more prominent, and the East and Southeast Asian markets are jointly contested by the major supply countries. This study can help to further understand the changing energy trade linkages and provide some reference for policy formulation to achieve energy trade security.
