Abstract: Ion chromatography (IC) was applied to the determination of some inorganic elements in aromatic polyamide fiber (Twaron).For the determination of anions,the sample in a platinum crucible was covered with Eschka mixture containing 3 parts of anhydrous Na2CO3 and 2 parts of zinc oxide,and heated in a muffle furnace at 450 ℃ for 1 h,some more of the Eschka mixture was added and heated at 850 ℃ for 1.5 h,to decompose the organic substance completely.The cooled melt in the crucible was dissolved in deionized water,and diluted to 100 mL in a volumetric flask with a mixed solution containing 18 mmol·L-1 Na2CO3 and 17 mmol·L-1 NaHCO3.This sample solution was used for IC determination of anions.For the IC-determination of cations (e.g.alkali metal and alkaline earth metal ions),the sample in the crucible was burned directly in a muffle furnace,without adding the Eschka mixture,until complete oxidation of the organic substances was attained.The residue in the crucible was treated ultrasonically with 1 mol·L-1 HNO3 or 1 mol·L-1 HCl,and transferred to a 100 mL volumetric flask,wash the crucible and diluted to 100 mL with deionized water.Working conditions of the IC determination were described,and the results of the 5 elements were found by the standard curve method.Detection limits for SO2-4,Na+,K+,Mg2+ and Ca2+ were found as 0.02,0.25,0.25,0.70 and 0.80 mg·L-1 respectively.