China's air quality reached its best levels on record during the 14th Five-Year Plan period (2021-25), as the country successfully balanced economic growth with air pollution control, according to the Ministry of Ecology and Environment.

China's GDP expanded by 30 percent, while the national average density of PM2.5 particulate matter fell by 20 percent over the past five years, Li Tianwei, head of the ministry's Department of Atmospheric Environment, said at a news conference on Friday.

During this time, the number of cities meeting national air quality standards increased from 206 to 246, he said.

Under the previous secondary standards introduced in 2012, the annual average concentration limit for PM2.5 was 35 micrograms per cubic meter. The ministry will implement upgraded standards for major air pollutants starting on March 1, with a transitional annual limit of 30 mcg/cu m for PM2.5 until 2030, before further tightening it to 25 mcg/cu m.

Li noted that among the current 29 cities with GDPs exceeding 1 trillion yuan ($145.8 billion), the average PM2.5 concentration is 27.8 mcg/cubic m, outperforming the national average.

"These cities all recorded significant improvements in air quality during the 14th Five-Year Plan period," he said. "Their tangible results demonstrate that economic growth and environmental protection can advance hand in hand."

Li highlighted the progress in Beijing, where, after 12 years of pollution control efforts, the average annual PM2.5 density dropped from 89.5 mcg/cu m in 2013 to 58 mcg/cu m in 2017, and further to 27 mcg/cu m in 2025.

Beijing's success "serves as a flagship achievement in China's air pollution control efforts", he said.

From July 20 to October 24, 2025, the proportion of days with fairly good air quality — considered below 100 on a 0-500 air quality index scale — nationwide exceeded 90 percent for 97 consecutive days, the first time such a duration has been recorded, he said.

In 2025, the average concentration of PM2.5 in cities at and above the prefecture level was 28 mcg/cu m, with the proportion of days with heavy pollution in these cities standing at 0.9 percent, he continued.

Excluding the impact of sand and dust weather, the proportion of days with fairly good air quality in these cities was 89.3 percent, Li added.

"All three indicators were the best on monitoring records," he said.