Oil and gas resources still occupy a dominant position in global energy consumption. China is the world’s largest energy consumption and oil importing country. Security of oil and gas resources supply is a major strategy related to national security. Based on the analysis of China’s overseas oil and gas dependence, this study summarized the main geographical risks of China’s oil and gas supply security and puts forward the countermeasures. The results show that: China’s dependence on overseas oil and natural gas has exceeded 70% and 40% respectively, and the concentration of importing countries is very high, which makes the country vulnerable to the interference of geopolitical risks. Potential geopolitical risks that China’s overseas oil and gas supply faces include the unstable geopolitical situation of importing countries, the possibility that the United States may use energy as a geopolitical tool and strategy, the concentration of new industrialized countries that have strong oil and gas demand. There are many strategic nodes in the oil and gas transportation channels that are easy to be interfered by the power of big countries. Strategic reserves of oil and gas are insufficient to deal with the risk of sudden war and embargo. To ensure China’s oil and gas security, it is necessary to adopt differentiated oil and gas cooperation strategies in view of the unstable situations in different regions.