Abstract: As the global climate change problem is becoming more and more serious, China has madethe commitment to the " dual-carbon" target. At present, our country has not fundamentally solved theissue of PM2.5 pollution. Meanwhile, O3 pollution is gradually worsening, and incidents of combinedPM2.5 and O3 occur frequently. Therefore, the sustained improvement of PM2.5 and O3 pollution is ofgreat significance to protect people's health and achieve carbon neutrality goals. To better understandand address PM2.5 pollution, this paper provides an overview of the effects of NOx and NH3 emissions,as well as secondary organic aerosols on PM2.5 pollution. Additionally, it summarizes current researchon the influence of emission sources (nitrogen oxides, volatile organic compounds) and meteorologicalfactors (temperature, relative humidity, UV radiation intensity, wind speed, boundary layer height,etc.) on O3 pollution in China, which provides methodological and theoretical support for improving O3pollution and developing reduction strategies in our country. Furthermore, this paper summarizes the re⁃search progress on the regional delineation, chemical mechanism and influencing factors of PM2.5 andO3 combined pollution in China, aiming to provide relevant references and guidance for China's followup action plan to improve air quality, protect the environment, and realize the synergistic managementof PM2.5 and O3 combined pollution under the " dual-carbon" policy.