Objective To establish a quantitative method to determine the content of platycodin D,D3 and E in Radix platycodi.Methods High performance liquid chromatagraphy-evaprorative light scattering dector(HPLC-ELSD) method was adopted.Platycodin D,D3 and E were separated by C18(5 ?m,4.6 mm?150 mm) with acetonitrile-water as mobile phase in a gradient program;flow rate was 1.0 mL/min,the temperature of drift tube was set at 113 ℃,and the gas flow(N2) was set at 3.0 L/min.Results The linear ranges of platycodin D,D3 and E were 13.78-275.6 ?g/mL(r=0.999 5),8.40-168.0 ?g/mL(r=0.999 7) and 12.02-240.4 ?g/mL(r=0.999 6),respectively.The average recoveries(n=5) were 98.3%,99.4% and 101.3%,respectively.Conclusion The method is convenient,accurate and reliable,and can be used for the determination of platycodin D,D3 and E in Radix platycodoi.