Abstract： Objective： To explore the medication rules and clinical experience of national famous Chinese medicine practitioner FAN Yongsheng in treating Sjögren syndrome．Methods：The cases with Sjögren syndrome who were treated at FAN Yongsheng National Famous Chinese Medicine Studio from January 2019 to February 2022 were collected．After screening the prescriptions that met the inclusion criteria，Excel was used to input relevant data for the interpretation of data， and a standardized medical case database was established． Using the Traditional Chinese Medicine Inheritance Computing System V3.5， association rules， cluster analyses and other methods were used to explore the medication characteristics and prescription rules．Results：A total of 107 cases and 272 prescriptions were included，involving 267 Chinese medicinals．Among them，eight high-frequency Chinese medicinals were used more than 100 times，including Poria，Glycyrrhizae Radix et Rhizoma，Citri Sarcodactylis Fructus，Ophiopogonis Radix， Atractylodis Macrocephalae Rhizoma，Paeoniae Radix Alba，Pseudostellariae Radix and Taraxaci Herba；the four qi was mainly neutral，（sweet）cold and warm；the five flavors were mainly sweet，bitter and acrid；the meridian entries were mainly the lung， liver， stomach and spleen； the function was mainly to supplement deficiency， clear heat， invigorate blood and resolve stasis，promote urination and percolate dampness；four main medicinal combinations were obtained by association rule analysis； four core medicinal groups were obtained by cluster analysis． Conclusion： Professor FAN used Chinese medicinals for supplementing deficiency，clearing heat，invigorating blood and resolving stasis， promoting urination and percolating dampness in terms of compatibility in the treatment of Sjögren syndrome， which reflects the core pathogenesis of “deficiency in root and excess in branch；qi-yin depletion and deficiency is the root and damp-heat stasis is the branch”．It should treat both the root and the branch by focusing on qi boosting and yin nourishing，supplemented by heat clearing，dampness draining and meridians dredgeing.