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<p>Gaseous pollutants at the ground level seriously threaten the urban air quality environment and public health. There are few estimates of gaseous pollutants that are spatially and temporally resolved and continuous across China. This study takes advantage of big data and artificial-intelligence technologies to generate seamless daily maps of three major ambient pollutant gases, i.e., NO<span class="inline-formula">₂</span>, SO<span class="inline-formula">₂</span>, and CO, across China from 2013 to 2020 at a uniform spatial resolution of 10 km. Cross-validation between our estimates and ground observations illustrated a high data quality on a daily basis for surface NO<span class="inline-formula">₂</span>, SO<span class="inline-formula">₂</span>, and CO concentrations, with mean coefficients of determination (root-mean-square errors) of 0.84 (7.99 <span class="inline-formula">µ</span>g m<span class="inline-formula">⁻³</span>), 0.84 (10.7 <span class="inline-formula">µ</span>g m<span class="inline-formula">⁻³</span>), and 0.80 (0.29 mg m<span class="inline-formula">⁻³</span>), respectively. We found that the COVID-19 lockdown had sustained impacts on gaseous pollutants, where surface CO recovered to its normal level in China on around the 34th day after the Lunar New Year, while surface SO<span class="inline-formula">₂</span> and NO<span class="inline-formula">₂</span> rebounded more than 2 times slower due to more CO emissions from residents' increased indoor cooking and atmospheric oxidation capacity. Surface NO<span class="inline-formula">₂</span>, SO<span class="inline-formula">₂</span>, and CO reached their peak annual concentrations of 21.3 <span class="inline-formula">±</span> 8.8 <span class="inline-formula">µ</span>g m<span class="inline-formula">⁻³</span>, 23.1 <span class="inline-formula">±</span> 13.3 <span class="inline-formula">µ</span>g m<span class="inline-formula">⁻³</span>, and 1.01 <span class="inline-formula">±</span> 0.29 mg m<span class="inline-formula">⁻³</span> in 2013, then continuously declined over time by 12 %, 55 %, and 17 %, respectively, until 2020. The declining rates were more prominent from 2013 to 2017 due to the sharper reductions in anthropogenic emissions but have slowed down in recent years. Nevertheless, people still suffer from high-frequency risk exposure to surface NO<span class="inline-formula">₂</span> in eastern China, while surface SO<span class="inline-formula">₂</span> and CO have almost reached the World Health Organization (WHO) recommended short-term air quality guidelines (AQG) level since 2018, benefiting from the implemented stricter “ultra-low” emission standards. This reconstructed dataset of surface gaseous pollutants will benefit future (especially short-term) air pollution and environmental health-related studies.</p>