In March, the average PM2.5 concentration in 339 prefecture-level and above cities nationwide was 31.5 micrograms per cubic meter, down 7.1% year-on-year; the average PM10 concentration was 54 micrograms per cubic meter, down 11.5% year-on-year; the average O3 concentration was 129 micrograms per cubic meter, up 5.7% year-on-year; the average SO2 concentration was 8 micrograms per cubic meter, flat year-on-year; the average NO2 concentration was 21 micrograms per cubic meter, a year-on-year decrease of 8.7%; and the average concentration of CO was 0.8 mg/m3, a year-on-year decrease of 11.1%.

In March, the average proportion of good air quality days in 339 cities at prefecture level and above nationwide was 86.6%, a year-on-year decrease of 3.8 percentage points, while the average proportion of days with heavy or above pollution was 2.0%, a year-on-year increase of 1.0 percentage point. The average proportion of days exceeding the standard caused by dusty weather was 7.4%, of which the proportion of heavily and above polluted days was 1.9%.

From January to March, the average concentration of PM2.5 in 339 cities at prefecture level and above nationwide was 41.3 micrograms per cubic meter, a year-on-year decrease of 4.8%; the average concentration of PM10 was 65 micrograms per cubic meter, a year-on-year decrease of 3.0%; the average concentration of O3 was 115 micrograms per cubic meter, a year-on-year increase of 3.6%; the average concentration of SO2 was 9 micrograms per cubic meter, a year-on-year flat; and the average concentration of NO2 was 7.4%. flat year-on-year; average NO2 concentration of 24 micrograms per cubic meter, down 4.0% year-on-year; and average CO concentration of 1.1 milligrams per cubic meter, down 8.3% year-on-year.

From January to March, the average proportion of good air quality days in 339 prefectural-level and above cities nationwide was 84.8%, up 1.2 percentage points year-on-year; the average proportion of days with heavy and above pollution was 1.8%, down 0.6 percentage points year-on-year. The average proportion of days exceeding the standard caused by dusty weather was 3.5%, of which the proportion of days with severe or above pollution was 0.9%.

Proportion of days at all levels in 339 cities at prefecture level and above nationwide in January-March 2025

List of Top 20 and Bottom 20 Cities in Air Quality Ranking of 168 Key Cities in January-March 2025

From January to March, among the 168 key cities, the top 20 cities with better air quality were, in order, Lhasa, Zhangjiakou, Haikou, Huizhou, Zhoushan, Xiamen, Fuzhou, Huangshan, Guiyang, Shenzhen, Ya'an, Lishui, Chengde, Zhuhai, Beijing, Kunming, Dongguan, Zhongshan, Dalian, and Zhaoqing; and the bottom 20 cities with worse air quality were, in order, Urumqi, Xianyang, Xi'an, Xiaogan, Xuzhou, Jingzhou, Xiangyang, Jining, Luohe, Heze, Harbin, Lanzhou, Linyi, Weinan, Shangqiu, Yuncheng, Nanyang, Huaibei, Xuchang and Zaozhuang.

From January to March, among the 168 key cities, the top 20 cities with better air quality changes are Baotou, Hohhot, Ya'an, Xinzhou, Shijiazhuang, Yangquan, Hebi, Handan, Linfen, Jiaozuo, Binzhou, Anyang, Xinxiang, Xingtai, Jinzhong, Puyang, Lvliang, Dongying, Zhengzhou and Leshan City; the bottom 20 cities with worse air quality changes are Yueyang, Xiangtan, Dongying, Zhengzhou and Leshan City. Yueyang, Xiangtan, Changsha, Zhuzhou, Jingzhou, Changde, Huanggang, Quzhou, Xiaogan, Xianning, Dazhou, Ezhou, Lu'an, Yichang, Urumqi, Changchun, Nanchang, Yiyang, Jinzhou and Bengbu.

From January to March, among the 168 key cities, the top 20 cities with lower PM2.5 concentrations were, in order, Lhasa, Zhangjiakou, Haikou, Shenzhen, Huizhou, Xiamen, Zhuhai, Zhoushan, Dongguan, Zhongshan, Chengde, Fuzhou, Guiyang, Guangzhou, Zhaoqing, Datong, Lishui, Beijing, Foshan and Shuozhou; and the bottom 20 cities with higher PM2.5 concentrations were, in order, Urumqi, Jingzhou, Yiyang, Jinzhou and Bengbu. Urumqi, Jingzhou, Xianyang, Xi'an, Shangqiu, Xiaogan, Luohe, Zhoukou, Harbin, Fuyang, Nanyang, Jingmen, Xuchang, Changde, Xiangyang, Huaibei, Yiyang, Huainan, Yichang and Kaifeng.

From January to March, among the 168 key cities, the top 20 cities with better changes in PM2.5 concentration were Baotou, Handan, Hohhot, Lvliang, Shijiazhuang, Linfen, Xingtai, Jiaozuo, Puyang, Hebi, Shuozhou, Yangquan, Dongying, Xinxiang, Ya'an, Datong, Pingdingshan, Binzhou, Xinzhou and Anyang City in order of priority; the bottom 20 cities with worse changes in PM2.5 concentration were Nanning and Beijing. 20 cities are Nanning, Yueyang, Changde, Urumqi, Suining, Xinyu, Changchun, Dazhou, Guang'an, Quzhou, Xiaogan, Zhuzhou, Ezhou, Xianning, Jingzhou, Chaoyang, Xiangtan, Wuhan, Anqing and Lu'an City in that order.

Source: Ministry of Ecology and Environment