In order to assess the quality of nano-TATB, a simple and rapid method for the determination of Cl^- and SO₄^2- in the absorbent liquid by oxygen flask combustion-ionic chromatogram was developed to monitor the trace component of TATB. Na₂CO₃ solution with a concentration of 4.7 mmol·mL^-1 was used as an eluate on an anion separation column of the model Metrosep A Supp 7 and conductivity detection. The method detection limits (MDL) of Cl^- and SO₄^2- were 0.0025 μg·mL^-1 and 0.0032 μg·mL^-1 respectively, under the optimized condition. The linear ranges of Cl^- and SO₄^2- were (500~3000) μg·L^-1 and (100~2500) μg·L^-1 respectively, and the correlation coefficients were all greater than 0.9990. The recoveries of the two analytes were 96.30%-103.73% and 97.23%-100.91% with the relative standard deviations (RSD, n=6) of 1.65%, 2.28%. The method has the advantage of simple operation, reagent-free and pollution-free, and can meet the quantitative analysis requirements of sulfur and chlorinous in nano-TATB.