Abstract: China's air environment has entered a new phase of severe PM_2.5 pollution and increasingly worsened O₃ pollution. Thus, the outline of the ‘14th Five-Year Plan’ proposed to promote the coordinated control of PM_2.5 and O₃ pollution. In contrast to the dual governance model of mitigation and adaptation being used in reaction to climate change, China has long regarded emission reduction as the only way to prevent pollution. Exploring the effect of adaptation besides abatement may be an economic approach for current pollution control. In June 2015, China's first Ecological Restoration and Urban Repair (also known as Urban Double Restoration (UDR)) pilot was launched in the city of Sanya, Hainan Province, which provides a natural experiment to examine the effect of adaptation on pollution. Using monthly urban air quality data from 2014-2016 as the measure, and based on geography, climate, and economic dimensions to screen Haikou from other cities in Hainan as a control city for Sanya, a difference-in-differences (DD) method has been built after performing the parallel trend test. Using the pre-pilot period as a temporal control for the post-pilot period, the DD specifications gradually controlling for atmospheric factors, fixed effects, a linear time trend, and a quadratic time trend identify the causal impact of the UDR pilot on air quality in Sanya. The results show that: (1) The UDR pilot significantly reduced Sanya's PM and O₃ pollution. The O₃ concentration was reduced by 30 μg/m³, PM_2.5 concentration was reduced by 7 μg/m³, and PM₁₀ concentration was reduced by 10 μg/m³, which was equivalent to a 47%, 39% and 28% reduction. (2) The UDR's effect on the reduction of O₃ concentration was persistent, and the effect on the reductions of PM was postponed for half a year. (3) The placebos that moved the URD pilot 6 months, 9 months, and 12 months ahead of schedule were found to not affect Sanya's air quality. This research suggests that the UDR pilot has an unexpected significant effect on the coordinated control of PM_2.5 and O₃ pollution in Sanya. Identifying the details of the restoration in different UDR phrases will help to accurately control PM_2.5 and O₃, and the promotion of these restoration details to other cities may facilitate mitigating the new air environment problems currently facing China.