ABSTRACT High O3 and PM2.5 concentrations were frequently observed in Jinan during June 2015 and simultaneously occurred on 8 days, with a maximum 8-hour-averaged O3 concentration of 255 µg m–3 and a maximum daily averaged PM2.5 concentration of 111 µg m–3. In order to investigate simultaneously controlling these two air pollutants, two simulation-based regional emission control experiments were designed using a nested air quality prediction model system (NAQPMS). One emission control scenario (“Conventional Control”) implemented the strictest control measures in Jinan and surrounding areas and resulted in a 15.7% reduction of O3 and a 21.3% reduction of PM2.5 on days polluted by O3 and PM2.5, respectively. The other emission control scenario (“Source-tagging Control”), by contrast, used online source-tagging modeling results from NAQPMS to select emission reduction regions based on their source contributions to the O3 and the PM2.5 in Jinan and resulted in a 16.2% reduction of O3 and a 22.8% reduction of PM2.5 on days polluted by O3 and PM2.5, respectively. Compared to Conventional Control, this scheme produced smaller reductions in emissions from areas with low contributions to the O3 and PM2.5 concentrations in Jinan as well as in the total emissions of primary pollutants (the reduced emissions was only 61% of that needed by Conventional Control), and the area and the population affected by these reductions decreased by 12% and 31%, respectively. However, this study demonstrates that Source-tagging Control is more efficient than Conventional Control in reducing simultaneous pollution by O3 and PM2.5 through regional measures.