In response to the severe haze pollution has become one of the major obstacles to the ecological integration development of the Yangtze River Economic Zone at presenta three-stage DEA model was used to study the haze management efficiency of 27 cities in the Yangtze River Delta from 2014 to 2019. The study shows that (1)Three-stage DEA model can effectively eliminate the effects of environmental factors and random errors, and can truly reflect the level of haze control efficiency in the Yangtze River Delta, and the difference between the integrated efficiency in the first and third stages is caused by environmental factors and random error factors affecting the pure technical efficiency. (2) The vast majority of cities are in increasing returns to scale, indicating that the improvement of haze control efficiency can be achieved by expanding the scale of haze control inputs.(3) The overall efficiency of haze control in Yangtze River Delta cities from 2014 to 2019 is high and shows a W-shaped change trend with intercity differences. (4) The increase in real GDP per capita and the share of secondary industry have positive effects on improving haze control efficiency, while the population size and urbanization rate have negative effects. Based on this, to further improve the level of haze management efficiency in Yangtze River Delta cities and promote the integrated ecological development of Yangtze River, we should increase technological innovation, create a diversified haze management funding model, and strengthen the level of collaborative management in Yangtze River Delta cities.