Objective:To establish an HPLC method for determination of chlorogenic acid,baicalin,emodin and chrysophanol contents in Kangjunxiaoyan tablet. Methods: After removing the coating,the powder of Kangjunxiaoyan tablet was extracted by 50% methanol for 30 min using the following condition: analytical column,Agilent Eclipse Plus-C18 column(4.6 mm×250 mm,5 μm); mobile phase:A,0.1% (v/v) phosphoric acid-water，B,methanol，C,acetonitrile with gradient elution. The flow rate was 0.8 ml/min; the detection wavelength was set at 254 nm; the temperature of column was 30℃; and the injection volume was 10 μl. Results: The title compounds were separated at baseline within 45 min with good linear,with the regression being Y=12.89X-12.66,r=0.999 9 for chlorogenic acid,Y=13.96X-1.013,r=1.000 0 for baicalin,Y=35.82X-4.923,r=0.999 9 for emodin,and Y=44.16X-3.280,r=0.999 9 for chrysophanol. The intra-day and inter-day precisions and the limits of detection were all within the normal range. The recovery rates(n=3) were:chlorogenic acid 101.5%(RSD=1.6%),baicalin 103.4%(RSD=1.4%),emodin 99.3%(RSD=2.0%),and chrysophanol 98.1%(RSD=1.7%). Conclusion: HPLC is a simple,accurate,stable,and reliable method in determining the contents of chlorogenic acid,baicalin,emodin,and chrysophanol in Kangjunxiaoyan tablet,and it can be used for quality control of this preparation.