Objective: To establish the optimum preparation process and investigate its dissolution of Osthole droping pills. Method: The proportion of osthole to matrix, processing temperature, drops distance and drops speed on the basis of the preliminary experiments were investigated with the spherical degree, the weight coefficient of variation, dissolved casual time and appearance evaluation of the dropping pills as the scoring indexes, and ultraviolet measuring technology was used to study its dissolution. Result: The optimal conditions were that proportion of matrix to osthole was 6 ∶1, matrix PEG3000:PEG6000 was 6 ∶1, processing temperature was at 60 ℃, drops rate at 12 d ·min-1 and 20cm distance above liquid level. Conclusion: The preparation method is simple, convenient and can be controlled easily. It is also consistent with the items on pills preparation requirements in Ch.P (2005). The dissolution of products is good.