Abstract: The particulate matter ejected from open sources has played an important role in urban atmospheric particulate matter(PM) pollution.The evaluation method relaed to the effects of PM from open sources to the urban ambient air quality is introduced.The PM jump-start wind speed,the diffusing distance,the amount of dust ejecting of the surface layer including the soil piles,coal piles,coal ash piles and sand piles in "S" city were measured and calculated by dynamics experience formulas.The total ejection from the open sources was calculated by Box model(A value).The contribution of the open sources to atmospheric PM was estimated by chemical mass balance(CMB) model.The result shows that in "S" city about 0.222 million tons per fear of PM <100 μm and 0.158 million tons per year of PM <10 μm are ejected from the open sources;about 60%(370 μg/m³) of TSP and 64%(263 μg/m³) of PM₁₀ derived from the open sources.