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By choosing the data of 7 basic weather stations and the Xi’an sounding station from 1971 to 2013, in combination with the manual observation of haze day records and the standards of visibility (less than 10 km and the relative humidity less than 80%), the temporal and spatial distribution characteristics of haze are analyzed on decadal, seasonal, and monthly scales, as well as the characteristics of wind, rainfall and boundary layer influencing factors when haze appears. The results show: (1) From the 1970s to 2000s, the decadal average number of haze days exhibited a decreaseincreasedecreaseincrease trend in Xi’an. (2) Xian is the main atmospheric pollution area in the Guanzhong area; the number of haze days in Xi’an showed a trend of rise; haze days appeared mainly in winter, and the vulnerable areas remained in the middle East; the influence of urbanization on haze days was significant, more obvious in the urban area and less in the suburbs. (3) The majority of haze weather lasts no more than a week; nearly 95% of haze weather occurred when the wind speed was under 33 m/s; the wind was less than level 1 in more than 50% of haze weather cases. (4) The number of haze days was inversely proportional to the number of rain days, proportional to the number of continuous no rainy days; the low monthly average number of longest continuous no rainy days appeared from April to September, and haze days are few. (5) The special basin topography, the climate trend of yearbyyear decreasing wind speed, and urban industrial pollution in Xi’an are important impact factors for haze weather and its fluctuations.