Abstract: The implement of "one belt and one road" program has made the starting station of the Silk Road Xi'an become the focus of the world. The air quality in Xi'an also attracts attention from the government and the public. Taking a strong dust period in northern China in May 2017 as a case, we firstly used the aerosol and atmospheric chemistry model developed by the Institute of Atmospheric Physics (IAP-AACM) to simulate the spatial and temporal distribution of fine particulate matter (PM_2.5) in the Central Shaanxi area. Combined with hourly surface PM_2.5 observation data, we explored the relationship between dust aerosol and the PM_2.5 simulation. Results show that adding the dust component to anthropogenic PM_2.5 significantly improves simulation accuracy, through which the correlation can be elevated by 0.4-0.6, and the sudden increase of PM_2.5 during the strong dust period can be well reproduced. During strong dust and general periods, the contribution of dust aerosol to PM_2.5 ranges from 60%-80% and 10%-30%, respectively. High-resolution simulations improve the model’s ability to capture the spatiotemporal changes of the pollutants.