OBJECTIVE：To establish a method for the determination of related substances in Lovastatin tablet. METHODS： HPLC was performed on the column of Waters XTerra® MS C18 with mobile phase A of 0.01％ Phosphoric acid solution and B of acetonitrile （gradient elution） at a flow rate 1.0 ml/min， column temperature was 40 ℃，the detection wavelength was 238 nm， and the injection volume was 10 μl. RESULTS： The impurity components were well separated in principal components； the linear range of lovastatin was 17.5-700 μg/ml （r＝0.999 9）； RSDs of precision， stability and reproducibility tests were lower than 1％； recovery was 99.30％-100.67％（RSD＝0.4％，n＝9）. CONCLUSIONS： The method is reproducible with good durability and high precision， and can be used for the quality control of Lovastatin tablet.