PM₁₀ samples were collected in summer in coal mine cities of Yima, Pingdingshan and Yongcheng, Henan Province. Scanning electron microscopy (SEM) equipped with X-ray Energy-dispersion spectroscopy (EDX) was employed to study composition, sources and origins of aerosol particles. The result indicates that, according to the chemical composition, aerosol particles can be divided into 5 kinds, i.e., "Si-rich", "Ca-rich", "S-rich", "K-rich" and "Cl-rich" types. Samples from Pingdingshan have abundant Si-rich particles, and their mineral particles had the lowest sulfatization. Samples from Yongcheng had a moderate degree of sulfatization, and the alkaline "Ca-rich" carbonate particles were mostly altered into gypsum through sulfatization. Samples from Yima experienced a very high degree of sulfatization, and certain amounts of mascagnite were formed besides gypsum. In addition, quite a few "K-rich" and "Cl-rich" grains were found in Yima and Yongcheng samples, respectively, probably attributed to straw-burning activities. Based on the difference in the mineral and chemical composition of the PM₁₀ samples, it is concluded that alkaline carbonate mineral, high sulfur coal, high SO₂ concentration resulting from straw burning and relatively high air humidity are beneficial to sulfatization of mineral particles, and sulfate particles have an important effect on the regional climate of coal-mine cities.