Objective: To establish the method of the dissolubility of puerarin in Yiyin Xiaoke Pills. Method: Basket-stirring method was used for the determination of in vitro dissolution and HPLC method was applied to determine the accumulated dissolution rate of puerarin at the different time. Result: The calibration curve was linear in the range of 88.4-2 210 μg

(r=0.999 9). The accumulated dissolution rate of puerarin in Yiyin Xiaoke pills reached 88.47% in 10min

while the accumulated dissolution rate of puerarin in capsule was only 0.25%. Conclusion: Yiyin Xiaoke pills can improve the dissolution rate of poorly soluble drugs of the kind of puerarin.