Abstract: To study a mixed serious pollution episode in Beijing in January 2013, TSP and PM₁₀ samples were collected on the roof of the Atmospheric Institute, Chinese Research Academy of Environmental Sciences, from December 31^st, 2012, to January 18^th, 2013. Elemental analysis results showed that the atmospheric pollution was induced under the meteorological conditions with temperature inversion and stable weather. The daily mean concentrations of TSP and PM₁₀ during the serious pollution period (January 11^th to 15^th) were 426.34 and 363.46 μg/m³, which were 3.5 and 3.4 times those during non-pollution period (2^nd to 6^th), respectively. Meanwhile, the total concentrations of inorganic elements in TSP and PM₁₀ during the serious pollution period (11^th to 15^th) were 36.38 and 18.67 μg/m³, which were 2.2 and 1.6 times those during non-pollution period and lower than the increases of total TSP and PM₁₀, respectively. Considering concentration characteristics and enrichment factor (EF), the crust-related elements represented by Na, Mg, Al, K, Ca and Fe had the highest mass concentration (>90%), and were not significantly increased during the serious pollution period. The EF of Mn, Cr and Ni not significantly vary during the studied episode. With higher concentration and greater EF, the elements Cd, Zn, As, Pb, Mo, Sn and Tl, whose mass fraction in PM₁₀ were 0.05%, 3.34%, 0.22%, 3.54%, 0.03%, 0.14% and 0.03% respectively, were mainly from coal-burning sources, vehicles, industrial source and waste incineration. In addition, the results also showed that the contribution of local sources slightly increased during serious pollution period.