Abstract: Petroleum, as a strategic mineral resource, plays a key role in China’s economic development and social stability. However, China’s external dependence on petroleum is expected to be around 74% in 2023, far exceeding the safety line of 50%. In this context, how to construct an evaluation index system for the security of China’s petroleum resource industry and supply chains has become an urgent problem to be solved. To this end, an evaluation index system is constructed from three levels: resource acquisition, resource circulation, and resource transformation. After rating and dividing the indicators from 2000 to 2021, a comprehensive analysis is conducted on both average and variable weights of the indicators to determine the changes in safety levels during the research period. Further analysis is conducted by combining obstacle and contribution models to identify factors that affect the safety of the industry and supply chains. The main research conclusions obtained are as follows: ① the supply chain security of China’s petroleum resource industry chain shows cyclical changes, and it is found that there are four small cycles that first increased and then decreased during the research period. At the same time, the entire research period also shows a trend of first increasing and then decreasing, indicating that although the supply chain security of China’s petroleum resource industry chain fluctuates, it is relatively stable around the center, and the fluctuations show cyclical fluctuations. ② The security of resource conversion is the main factor hindering the security of China’s petroleum resource industry chain and supply chain, which is related to China’s lower position in the petroleum resource industry chain and can affect the security of resource acquisition and circulation. ③ The main contributing factors to the security of the petroleum resource industry chain and supply chain are relatively complex. In the first cycle, circulation safety and conversion safety are the main contributing factors, conversion safety is the second cycle, circulation safety is the third cycle, and the contribution of the three factors is relatively equal in the fourth cycle. Based on the above conclusions, policy recommendations are provided for the security of the petroleum resource industry chain and supply chain from three aspects: resource acquisition, resource circulation, and resource transformation. This paper proposes directions and ideas for maintaining the security of China’s petroleum resources, and contributes to enhancing the security of the industry and supply chains.