Is the air quality good in Chengdu?
On September 4, 2025, at 11:50 PM PT, Chengdu, China, is experiencing poor air quality due to regional emissions and weather conditions. The AQI is over 140, classified as "unhealthy for sensitive groups," with PM2.5 concentrations dominating.
These conditions can cause respiratory issues, worsen heart problems, and impair lung function, especially for children, the elderly, and those with health vulnerabilities.
To stay safe during this temporary spike, limit outdoor time, seal windows, wear masks if venturing out, and use air purifiers indoors for cleaner breathing air.
Air quality is dynamic and, like the weather, can change frequently. Chengdu ranked 3rd among the most polluted cities in the world on Friday afternoon (local time), with nearby cities like Chongqing also affected.
Click here for a real-time air quality map of Chengdu.
While the air quality conditions today are unusually poor, it is important to keep in mind that the average PM2.5 concentration in 2024 for Chengdu was 32 µg/m³. This corresponded to an AQI of 90, which falls into the “moderate” category and was already 6.4 times the WHO annual guideline of 5 µg/m³.
By comparison, today’s AQI is near 150, placing it in the “unhealthy” range. This shows that air quality in Chengdu has worsened significantly, with current conditions posing clear health risks for sensitive groups and even the general population.
Chengdu, China ranked as the 3rd most polluted major city on Sept 5, 2025. Source: IQAir.
When will the air quality improve in Chengdu?
Air quality is forecasted to improve gradually in coming days as winds pick up and help disperse pollutants, with conditions potentially dipping into the “moderate” range. However, these improvements may fluctuate depending on weather patterns such as temperature shifts and rainfall.
In the long term, Chengdu faces deeper structural challenges, its valley geography and ongoing emissions from traffic and industry mean that without targeted action, lasting progress will be limited.
For today, however, the hourly forecast shows air quality continuing to worsen.
Hourly air quality forecast for Chengdu, China on Sept 5, 2025. Source: IQAir.
Air quality map of Chengdu, China on Sept 5, 2025. Source: IQAir.
What is causing poor air quality in Chengdu?
Chengdu’s poor air quality is the result of a mix of regional and urban factors. The city is located within the Sichuan Basin, where surrounding mountains limit wind flow and trap pollutants such as vehicle exhaust and haze over the area (1).
Rapid urban growth has also led to a sharp increase in vehicles on the roads, with emissions from cars, trucks, and buses contributing heavily to particulate pollution. In addition, the industrial sector, much of which is still coal-based, emits large volumes of fine particles (2).
Ongoing urbanization, population growth, and rising energy demand further add to the problem. These structural and climatic conditions together make it difficult for Chengdu’s air to naturally clear itself.
How can I protect myself from poor air quality?
- Get a free air quality app for real-time air quality alerts and forecasts.
- Shut doors and windows and set the HVAC to recirculate mode.
- Contribute to your community’s outdoor air quality data.
- Stay indoors when air quality is poor; if you do need to go outdoors, wear a KN95/FFP2 mask.
- Run a high-performance air purifier to filter particles, gases, and other pollutants.
