<p>Fine particulate matter (PM<sub>2.5</sub>) is a severe air pollution problem in China. Observations of PM<sub>2.5</sub> have been available since 2013 from a large network operated by the China National Environmental Monitoring Center (CNEMC). The data show a general 30–50 % decrease of annual mean PM<sub>2.5</sub> across China over the 2013–2018 period, averaging 5.2 μg m<sup>−3</sup> a<sup>−1</sup>. Trends in the five megacity cluster regions targeted by the government for air quality control are 9.3 ± 1.8 μg m<sup>−3</sup> a<sup>−1</sup> (±95 % confidence interval) for Beijing-Tianjin-Hebei, 6.1 ± 1.1 μg m<sup>−3</sup> a<sup>−1</sup> for Yangtze River Delta, 2.7 ± 0.8 μg m<sup>−3</sup> a<sup>−1</sup> for Pearl River Delta, 6.7 ± 1.3 μg m<sup>−3</sup> a<sup>−1</sup> for Sichuan Basin, and 6.5 ± 2.5 μg m<sup>−3</sup> a<sup>−1</sup> for Fenwei Plain (Xi'an). Concurrent 2013–2018 observations of sulfur dioxide (SO<sub>2</sub>) and CO show that the declines in PM<sub>2.5</sub> are qualitatively consistent with drastic controls of emissions from coal combustion. However, there is also a large meteorologically driven interannual variability of PM<sub>2.5</sub> that complicates trend attribution. We used a stepwise multiple linear regression (MLR) model to quantify this meteorological contribution to the PM<sub>2.5</sub> trends across China. The MLR model correlates the 10-day PM<sub>2.5</sub> anomalies to wind speed, precipitation, relative humidity, temperature, and 850 hPa meridional wind velocity (V850). We find that meteorology made a minor but significant contribution to the observed 2013–2018 PM<sub>2.5</sub> trends across China and that removing this influence reduces the uncertainty on the emission-driven trends. The mean PM<sub>2.5</sub> decrease across China is 4.6 μg m<sup>−3</sup> a<sup>−1</sup> in the meteorology-corrected data, 12 % weaker than in the original data. The residual trends in the five megacity clusters attributable to changes in anthropogenic emission are 8.0 ± 1.1 μg m<sup>−3</sup> a<sup>−1</sup> for Beijing-Tianjin-Hebei (14 % weaker than the observed trend), 6.3 ± 0.9 μg m<sup>−3</sup> a<sup>−1</sup> for Yangtze River Delta (3 % stronger), 2.2 ± 0.5 μg m<sup>−3</sup> a<sup>−1</sup> for Pearl River Delta (19 % weaker), 4.9 ± 0.9 μg m<sup>−3</sup> a<sup>−1</sup> for Sichuan Basin (27 % weaker), and 4.9 ± 1.9 μg m<sup>−3</sup> a<sup>−1</sup> for Fenwei Plain (Xi'an; 25 % weaker). 2015–2017 observations of flattening PM<sub>2.5</sub> in the Pearl River Delta, and increase in the Fenwei Plain, can be attributed to meteorology rather than to relaxation of emission controls.</p>