目的 制备3种中药浙贝母、天麻和红景天的最细粉，比较不同粒径的中药粉体的理化性质差异。方法 分别制备浙贝母、天麻和红景天最细粉，对其粒径、形貌结构、流动性、吸湿性等粉体学特征以及醇溶性浸出物的量和有效成分的量进行考察。结果 药材经过粉碎后，3种中药材的粉体学性质及醇溶性浸出物和有效成分的量均发生一定的改变。随着粒径的减小，中药粉体的比表面积增加，流动性稍有降低，吸湿性稍有增加，醇溶性浸出物的量和有效成分的量均有所提高。结论 3种中药材经过粉碎后，粉体学性质有所改变，能够促进药材中有效成分的溶出，为中药最细粉的入药提供了实验依据。

Objective To prepare the three kinds of superfine powder of Fritillariae Thunbergii Bulbus (FTB), Gastrodiae Radix (GR), and Rhodiolae Crenulateae Radix et Rhizoma (RCRR) and compare the differences of their physicochemical properties in different patical diameters of Chinese materia medica (CMM) powder. Methods The superfine powder of FTB, GR, and RCRR was prepared to investigate the powder characteristics for the particle diameters, powder morphology, liquidity, and hygroscopicity. Furthermore, the ethanol extract and the effective ingredient content were quantified to evaluate the impact of particle diameters on the physicochemical properties of FTB, GR, and RCRR. Results There were differences between the common and superfine powder in physicochemical characteristics. With the decreasing of particle diameters of FTB, GR, and RCRR powder, both the specific surface area and the moisture increased while the liquidity decreased slightly. The alcohol soluble extract and effective ingredient content increased. Conclusion After superfine grinding, the powder properties of FTB, GR, and RCRR superfine powder are changed, the dissolution of effective ingredient is promoted, which provides the experimental references for the further study on the superfine powder of CMM.