Due to the fact that a synergistic efficiency enhancement of pollution and carbon emissions reduction is the prerequisite for China to achieve the dual-carbon goal, and an establishment of the carbon market is an important means for this purpose, it is of great practical significance to study the impact of the carbon market on pollution reduction and carbon synergy. Taking the carbon emissions trading system as a quasi-natural experiment, based on the panel data of 30 provinces and municipalities from 2005 to 2021, an investigation has thus been made of the implementation effect of the carbon emissions trading system on the synergistic governance of pollution and carbon emissions reduction by adopting a double-difference method. The results show that the implementation of the carbon emissions trading system can effectively promote the synergistic governance of pollution and carbon emissions reduction; the promotion effect is mainly achieved by a reduction the scale of energy consumption, an improvement of the level of green technology innovation, and an optimization of the industrial structure; the promotion effect of the policy on the synergistic governance of pollution and carbon emissions reduction will be stronger in regions with higher levels of administrative intervention and marketisation. Based on this point, it is recommended to improve the construction of the national carbon emissions trading market in light of practical needs, increase investment in scientific and technological research and development as well as investment in pollution control, correctly handle the relationship between the government and the carbon market, and maximize the role of government intervention in the carbon market mechanism.