In order to further determine the mass concentration and ion composition of size-segregated particulate matter (PM) during the non-Asian dust storm of spring, PM2.5 (fine particle), PM10-2.5 (coarse particle), and PMover-10 (PM with an aerodynamic diameter larger than 10 ㎛) were collected using a MCI (multi-nozzle cascade impactor) sampler of a three-stage filter pack in the spring season of 2007 in the Iksan area. During the sampling period from 5 April to 21 April, a total of 34 samples for size-segregated PM were collected, and then measured for PM mass concentrations by gravimetric measurements and for water-soluble inorganic ion species by using ion chromatography. Average mass concentrations of PM2.5, PM10-2.5, PMover-10 were 35.4±11.5 ㎍/m³, 13.3±5.5 ㎍/m³, and 9.5±4.7 ㎍/m³, respectively. On average, PM2.5 accounted for 74% of PM10. Compared with the literature from other areas in Korea, the measured concentration of PM2.5 were relatively high. Water-soluble inorganic ion fractions in PM2.5, PM10-2.5, and PMover-10 were found to be 47.8%, 28.5%, and 14.7%, respectively. Among the water-soluble inorganic ion species, SO₄²-, NO₃-, and NH₄+ were the main components in PM2.5, while NO₃- dominantly existed in both PM10-2.5 and PMover-10. Non-seasalt SO₄²- (nss- SO₄²-) and NO₃- were found to mainly exist as the neutralized chemical components of (NH₄)₂ SO₄ and NH₄NO₃ in fine particles.