Abstract: The plant sample was combusted in oxygen bomb, and the HCl and SO3 evolved were absorbed in a mixed solution of 0.08 mol·L-1 Na2CO3, 0.01 mol·L-1 NaHCO3 and H2O2. The contents of chloride and sulfur in absorption solution were determined by IC. Ionpac AS14A (4 mm×250 mm) column was used as ion exchange column, and a mixture of 0.008 mol·L-1 Na2CO3 and 0.001 mol·L-1 NaHCO3 was used as eluent. Values of detection limits (3S/N) of the method found were 0.04 mg·L-1 for S and 0.02 mg·L-1 for Cl. The proposed method has been used in the analysis of the standard samples of rice (GSB-1S), soybean (GSB-4S), spinach (GSB-6S) and cabbage (GSB-5S), the results obtained were in conformity with their certified values. Values of RSD′s (n=5) and recovery found were 4.2%, 97.0% for S and 3.1%, 93.8% for Cl respectively.