AIM: To study the application of superfine comminution in Renzhujianwei Granule. METHODS: After being pretreated, Rhizoma Altractylodis macroleplea and coix seed were crushed into ultra-fine powder by TC20 medical superfine crusher. Then the ultra-fine powder was made into the granule. RESULTS: Detected by scanning electron microscope and EDS X-ray detector, the mean diameter of the particle was ≤5 ?m; The detection of the normal distribution was 87.93%≤20 ?m and 95.08%≤20 ?m. CONCLUSION: The application of ultra-fine powder in Renzhujianwei Granule develops a new method of producing granule, that can save the pharmaceatic adjuvants and keep the effective components, and is propitious to the molding of the preparation, and also can improve the stability.