This thesis analyses the formation of haze by taking the case of severer haze in Beijing in the winter of 2015, which was caused by the collective effect of human activities, topography and meteorological. Among these causes, anthropogenic emissions contributed most, such as coal-fired emissions and vehicle emissions. The haze not only brings direct harm to health, but also slowly changes the way people live in the haze. Beijing has issued the Clean Air Action Plan to mitigate haze. Additionally, a series of stringent control measures were adopted during Beijing Olympics and APEC summit. These measures, such as vehicle emissions reduction and coal-free programme effectively reduced the PM concentration but failed to reduce GHG emissions. Hence, the causes for the lack of sustainability of air pollution control measures are included in thesis.