Objective: To investigate influence of different proportions between Puerariae Lobatae Radix and Ephedrae Herba on dissolution of puerarin. Method: HPLC was used to determine the content of puerarin with mobile phase of methanol-water (25:75) and detection wavelength at 250 nm

methodological study of puerarin from couplet medicines of Puerariae Lobatae Radix and Ephedrae Herba was established.Effects of couplet medicines of Puerariae Lobatae Radix and Ephedrae Herba with different proportions (3:1

2:1

4:3

1:1

1:2

1:3) on dissolution of puerarin were investigated. Result: This established determination was stable and feasbile with average recovery of 99.67% (RSD 2.2%).The maximum dissolution (2.408 g· L-1) of puerarin was achieved when proportions of Puerariae Lobatae Radix and Ephedrae Herba was 4:3

it was closed to Puerariae Lobatae Radix decoction (2.455 g· L-1)

the minimum dissolution (2.254 g· L-1) of puerarin was achieved when proportions of Puerariae Lobatae Radix and Ephedrae Herba was 2:1. Conclusion: Different proportions of Puerariae Lobatae Radix and Ephedrae Herba had some influence on dissolution of puerarin.