Abstract: With the rapid development of social economy and increase of pollution source emissions, the frequent occurrence of haze makes air quality is getting worse. The occurrence of haze weather and weather conditions are strongly coupled. GPS technology provides a new means for sensing atmosphere water vapor with the advantages of high precision, high temporal resolution, automatic real time, all-weather and high reliability et al. Firstly the inter-relations for forming reasons and the change role of dust-haze weather have been statistically analyzed in this paper, then GPS water vapor, haze weather index and air relative humidity have been quantitatively analyzed. Analysis Results show that there is a certain correlation between the GPS water vapor and the formation of haze weather. GPS water vapor may be used to monitor and forecast the form of haze weather. In order to degrade the effect of continuous dust-haze and improve air quality, meteorological department also plans to carry out artificial precipitation (snow) with valuable GPS water vapor.