In order to investigate the characteristics of PM(sub)2.5 in the background area, the following pollutant were measured from February 1996 to June 1999 in Kanghwa: PM(sub)2.5 mass, sulfate, nitrate, chloride, ammonium, sodium, calcium, magnesium and potassium. The mean concentration of PM(sub)2.5 mass was 25.8$pm$1.2$mu extrm{g}$/㎥(range 5.18~85.74). This value was higher than the annual PM(sub)2.5 US NAAQS(15$mu extrm{g}$/㎥) and the total number of samples higher than the 24-h PM(sub)2.5 US NAAQS(65$mu extrm{g}$/㎥) was seven. PM(sub)2.5 masses also showed temporal variations both yearly and seasonally. Total water soluble ions constituted about 45% of PM(sub)2.5 miss, and sulfate, nitrate and ammonium were main components in water soluble ions. Compared with the literature data from other areas, the measured PM(sub)2.5 concentrations were relatively high.