Particulate matter (PM) pollution from pig farms is of increasing environmental concern due to the rapid development of intensively managed pig farms worldwide. However, information on this topic is scarce in China to date. Therefore a two-year study to monitor the dynamics of total suspended particles (TSP) and particulate matter with diameter less than 10 μm (PM₁₀) and their soluble ions was conducted at an industrial pig farm near Beijing. In total, two fattening pig houses were sampled during three fattening periods from 2010 to 2011. Daily mean indoor TSP and PM10 concentrations were 1.85 and 0.63 mg m–3 on average. The emissions of PM per livestock unit (LU unit =500 kg), and per unit area (m2) from the pig house averaged 467.5 mg h^–1 LU^–1 and 38.6 mg h^–1 m^–2 for TSP, while those for PM10 averaged 256.7 mg h^–1 LU^–1 and 16.8 mg h^–1 m^–2, respectively. Particulate NH^{4 +} in both TSP and PM10 showed significant positive correlations with particulate NO^{3 –} and SO₄^2– inside and outside the pig houses. Daily mean indoor concentrations of secondary inorganic aerosol (sum of NH^{4 +}, NO^{3 –} and SO₄²–) ranged from 10.8 to 368.8 μg m^–3 (average 116 μg m^–3) in TSP and from 5.1 to 220.1 μg m^–3 (average 58.6 μg m^–3) in PM₁₀. Contributions of secondary inorganic PM to TSP and PM₁₀ emissions varied from 0.3 to 50.8% and from 1.0 to 48.7%, respectively, with averages of 12.0 and 13.9%. Our results suggest elevated PM and secondary inorganic PM concentrations and substantial emissions of PM from the fattening pig houses in China.