In order to evaluate the toxicity of the airborne particles in Beijing during the pollution process, the authors collected the PM₁₀(particulate matter with aerodynamic diameters of less than 10 μm) in the urban area of Beijing in 2016 and analyzed the oxidative capacity of the particles by plasmid scission assay. The results indicated that the oxidative capacity of PM₁₀ during the haze was higher than that after haze, and both were higher than that before the haze. In addition, the damage rate of supercoiled DNA by the samples increased with increasing experimental dose levels. The TD₂₀ values of the PM samples before, during, and after the haze displayed a descending order of before haze (788.01 μg/mL) > after haze (470.40 μg/mL) > during haze (55.78 μg/mL), which indicated a descending order of the PM oxidative capacity of during haze>after haze>before haze. The TI value during haze was higher than that after haze, both were higher than that before haze, suggesting that the PM₁₀ during haze was more harmful to human health.