To investigate the levels and size distributions of water soluble inorganic components, samples were collected with Andersen cascade sampler from Feb. 2011 to Feb. 2012, in Fukang, and were analyzed by IC. The variation trend, concentration level, composition, sources and size distribution of major ions during non-heating period were compared with heating period. Based on the specific samples, ionic compositions and size distributions were analyzed during heavy pollution, straw burning and spring planting periods. The results showed that inorganic components in Fukang were severely affected by heating. The total water soluble ions in fine and coarse particles during non-heating and heating periods were 11.17, 12.68 microg x m(-3) and 35.98, 22.22 microg x m(-3), respectively. SO4(2-) was mainly from saline-alkali soil, NO3(-) and NH4(+) were from resuspension of farmland soil during non-heating period, while SO4(2-), NO3(-) and NH4(+) were all from the fossil fuel consumption during the heating period. All ions were bimodal distribution during non-heating and heating periods. During the heating period, the particle size growth of SO4(2-), NO3(-) and NH4(+) in fine mode was found, SO4(2-) and NH4(+) peaked at 3.3-4.7 microm in coarse particles. Secondary pollutions were serious during heavy pollution days with high levels of secondary ions between 1.1 and 2.1 microm. Biomass burning obviously affected the size distribution of ions during the straw burning period and ions focused on smaller than 0.65 microm, while there were more soil dusts during spring planting periods and ions concentrated in larger than 3.3 microm.