In recent years, state-owned enterprises have attracted more and more attention in the field of international trade. On the one hand, the share and importance of state-owned enterprises in international trade have become more and more significant. On the other hand, the existence of state ownership makes state-owned enterprises different from general market players as state-owned enterprises are relatively easier to obtain unfair competitive advantages. Against this background, the Trans-Pacific Partnership (TPP) created a chapter on state-owned enterprises for the first time, setting additional rules for state-owned enterprises. Although TPP was eventually aborted, the state-owned enterprise chapter was fully retained by the Comprehensive Progressive Trans-Pacific Partnership (CPTPP). On September 16th, 2021, China officially applied to join CPTPP. State-owned enterprises play an important role in China’s national economy, and strict rules for state-owned enterprises will be a major challenge for China to join CPTPP. This paper mainly adopts the normative analysis method to conduct a detailed study of state-owned enterprise rules of CPTPP, and compares them with the existing WTO rules to clarify the differences between the old and new rules. In comparison, CPTPP has expanded the scope of state-owned enterprises, included more enterprises in the regulation of the state-owned enterprise chapter, and set up subsidy rules specifically for state-owned enterprises, bypassing the originally controversial issue of public body. In addition, commercial consideration has become an independent obligation of state-owned enterprises, and the transparency rules have also been strengthened to a certain extent. In fact, the requirements of the CPTPP state-owned enterprise rules and the principle of competition neutrality behind them are consistent with the goals of China’s ongoing state-owned enterprise reform. However, in the past, China’s state-owned enterprise reform paid little attention to the constraints of the international market, which resulted in a failure to achieve a good connection between domestic and international rules. Joining CPTPP this time will be a good opportunity to promote the reform of state-owned enterprises in China. This article combines the new regulations of CPTPP with the current situation in China, and provides detailed suggestions for China to address the challenges of the CPTPP chapter on state-owned enterprises. Compared with previous literature, this article expands on specific suggestions for China’s response to CPTPP rules of state-owned enterprises. There is little existing research that combines the study of the CPTPP rules with the reality of China’s reform, and the countermeasures proposed to address the challenges brought by rules of state-owned enterprises in CPTPP and other new free trade agreements are mostly principled. This article analyzes the relevant regulations and documents related to state-owned enterprises in China, compares the differences between domestic rules and CPTPP rules, and proposes specific and more targeted suggestions for the reform of state-owned enterprises in China. After TPP, the chapter on state-owned enterprises emerged in various bilateral and regional trade agreements. Under multilateral trade rules, the issue of state-owned enterprise is also one of the focuses of WTO reform. The research in this article will help China deepen the reform of state-owned enterprises, reduce the resistance to joining the CPTPP, and have strong practical significance for China’s subsequent WTO reform negotiations and participation in the formulation of new international trade regulations.