Fiscal decentralization, as a model of distributing power and resources between the central and local governments, has complex and profound implications for the governance and control of atmospheric environmental pollution. The article explores the relationship between fiscal decentralization and atmospheric environmental pollution, utilizing panel data from 31 provinces in China from 2009 to 2021 to construct fixed-effect models for empirical analysis. The findings reveal a significant positive correlation between fiscal decentralization and atmospheric environmental pollution, which suggests that fiscal decentralization leads to environmental pollution. Robustness tests, including considerations for the COVID-19 pandemic shock, consistently validate the accuracy of the regression conclusions. The article further analyzes whether there are regional differences in the impact of fiscal decentralization on atmospheric environmental pollution in China by introducing the cross-multiplier terms for directly administered municipalities and autonomous regions, and the results show that there are regional differences in the impact of fiscal decentralization on atmospheric environmental pollution in directly administered municipalities, and that an increase in fiscal decentralization is conducive to the improvement of environmental quality in the directly administered municipalities. In contrast, autonomous regions exhibit the opposite trend, as their fiscal decentralization has a more significant adverse impact on atmospheric environmental pollution compared to other provinces. In conclusion, the article suggests that for the key and difficult areas of air pollution in China, it is necessary to rationalize the fiscal allocation of local governments and strengthen the mechanism of local environmental governance responsibility, in order to promote the coordinated development of regional economy and environment.