Abstract: A new air pollution emission inventory of Hebei Province during the 2008 Beijing Olympic Games is generated on the basis of previous Beijing real-time forecast emission inventory from Wang et al.(2006), considering updated emission data and pollution control measures. Then with the help of Nested Air Quality Prediction Model System(NAQPMS), regional air quality simulation is processed to evaluate the updated pollution intensity and its effect. After comprehensive comparison between model outputs and measurements such as ground observation and satellite data from space, it is confirmed that the update efforts are resultful to some extent, especially on some primary species such as SO2. And a series of pollution control policies are believed to make a crucial contribution, shown by scenario analysis, to the air quality improvement during the Beijing Olympics.