OBJECTIVE： To improve the determination method for the contents of main components and related substances in Loxoprofen sodium tablets. METHODS： RP-HPLC method was adopted. The determination was performed on Inspire C18 column with mobile phase consisted of acetonitile-0.01 mol/L potassium dihydrogen phosphate （containing 0.2％ triethylamine， phosphoric acid adjusted to 3.0±0.1，62 ∶ 38，V/V） at the flow rate of 1.0 mL/min. The column temperature was 40 ℃， and the detection wavelength was set at 221 nm. The sample size was 20 μL. RESULTS： The peak of loxoprofen sodium was well separated with the peak of its related substances （R＞1.5）. The linear range of loxoprofen sodium ranged 30.0-90.0 μg/mL （r＝0.999 8）. The detection limit of loxoprofen was 0.3 μg/mL. RSDs of precision， stability and repeatability tests were ＜1.0％. The average recovery rates ranged 99.00％-99.87％ （RSD＝0.33％，n＝9）. CONCLUSIONS： This method is accurate， simple， rapid and suitable for the quality control of Loxoprofen sodium tablets.