OBJECTIVE： To improve HPLC for the contents determination of 2-methyl-5-methoxy-indole-3-acetic acid （impurity Ⅰ） and 4-chlorobenzoic （impurity Ⅱ） in Indometacin enteric-coated tablet. METHODS： The column was Phenomenex Phenyl-Hexyl with mobile phase of 10 g/L acetic acid solution - acetonitrile （gradient elution） at a flow rate of 1.0 ml/min， the detection wavelength was 254 nm， column temperature was 40℃， injection volume was 20 μl. RESULTS： The linear range was 0.262 2-5.243 0 μg/ml for impurity Ⅰ （r＝0.999 8） and 0.252 5-5.050 0 μg/ml for impurity Ⅱ （r＝0.999 8）； the limits of quantitation were 1.12 ng and 0.48 ng， limits of detection were 0.340 ng and 0.146 ng， respectively； RSDs of precision， stability and reproducibility tests were lower than 2％； recoveries were 99.71％-100.52％ （RSD＝0.28％，n＝9） and 100.84％-102.14％（RSD＝0.47％，n＝9）. CONCLUSIONS： The method is accurate and rapid， and can be used for the contents determination of impurity Ⅰ and impurity Ⅱ in Indometacin enteric-coated tablet.