The majority of the air pollution in China is generated by the burning of coal (and a bit of fuel oil) to generate electric power. They do not have that much hydropower to help with demand, and they rely on the burning of coal. It's available locally in good quantity, and only a few hundred Chinese miners die every year to keep it coming out of the ground. China burns more coal to produce electricity than the U.S., Europe and Japan combined. Air pollution and acid rain (from coal's sulfur - which is oxidized to sulfur dioxide during combustion) are killing people - literally. Cancer is the leading cause of death in China, and pollution of the air and water is the leading cause of cancer there. Lots and lots of cars burning poor quality fuel add to urban air pollution. Levels of particulate matter in the air of urban areas are three times what is "unacceptable" in the European Union.

Q- What is causing the pollution in china?
A- They burn fuel,oil, coal, etc. Another big thing is vehicles, hundreds of thousands of people drive in China.