On the CCN(Cloud Condensation Nuclei)condition of mineral aerosols coated with(NH₄)₂SO₄ by heterogeneous-phase chemical processes,the rule of the condensation growth process of droplets is discussed first.Based on the aerosol and cloud droplet size distribution data measured in the aerial survey in Liaoning on May 14,1997,the cloud drop size distributions are calculated for mineral aerosols coated with(NH₄)₂SO₄ and pure(NH₄)₂SO₄ nuclei,respectively.Comparison shows that the cloud drop size distributions for mineral aerosol coated with(NH₄)₂SO₄ are wider than the ones for pure(NH₄)₂SO₄ nuclei,and the former is in agreement better well with the observation than the latter.