Abstract: Coal consumption is the main source of SO₂, NO_x and particulate matter emissions, and half the world's coal combustion is in China, leading to huge emission of waste gas volume and pollutants. Although the emission standards have been gradually stricter in related industries, under the same emission standard limits, the total emissions of various pollutants are determined by the waste gas volumes. The technologies of waste gas volume reduction including waste gas recycling and cascade utilization in cement industry and iron and steel industry were introduced in detail. Also, the potential of waste gas volume reduction was analyzed. The results showed that the reduction in waste gas volume could significantly reduce the total pollutant emissions, which should provide a new strategy to realize advanced pollutant emission reduction and to prevent and control the haze problem.