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Economic activities and the associated emissions have significantly declined during the 2019 novel coronavirus (COVID‐19) pandemic, which has created a natural experiment to assess the impact of the emitted precursor control policy on ozone (O3) pollution. In this study, we utilized comprehensive satellite, ground‐level observations, and source‐oriented chemical transport modeling to investigate the O3 variations during the COVID‐19 pandemic in China. Here, we found that the significant elevated O3 in the North China Plain (40%) and Yangtze River Delta (35%) were mainly attributed to the enhanced atmospheric oxidation capacity (AOC) in these regions, associated with the meteorology and emission reduction during lockdown. Besides, O3 formation regimes shifted from VOC‐limited regimes to NOx‐limited and transition regimes with the decline of NOx during lockdown. We suggest that future O3 control policies should comprehensively consider the effects of AOC on the O3 elevation and coordinated regulations of the O3 precursor emissions. Plain Language Summary: Severe ozone (O3) pollution has been a public concern in China during the last decade. Due to the 2019 novel coronavirus (COVID‐19) pandemic, China has implemented the strict restrictions, leading to the significant decline of economic activities and the associated emissions. However, the O3 levels have been elevated in vast areas of China during the COVID‐19 lockdown period. In this study, we applied the comprehensive satellite, ground‐level observations, and source‐oriented chemical transport modeling to investigate the O3 elevation during the COVID‐19 lockdown periods. Importantly, our results showed that O3 has increased significantly in North China Plain (40%) and Yangtze River Delta (35%) during lockdown, which attributed to the enhanced atmospheric oxidation capacity (AOC) associated with the meteorology and emission reduction. Besides, we found the O3 formation regimes shifted from VOC‐limited to NOx‐limited due to the lower NOx during lockdown. In the future, we suggest that O3 control policies ought to ensure a balance between emitted NOx and VOCs to maintain stable O3 formation regimes and AOC levels and thereby control O3 emissions. Key Points: O3 formation regime shift from a VOC‐limited to a NOx‐limited regime has been found in most areas of ChinaEnhanced atmospheric oxidation capacity (AOC) contributed to O3 elevation during COVID‐19 lockdownO3 control policies should consider from the comprehensive sights of O3 formation regime and AOC in the future [ABSTRACT FROM AUTHOR]