To study the effects on phosphorylation (pSTAT6) level of signal transducer and activator of transcription 6 (STAT6) and the expressions of andSTAT6 mRNA,IL-4 mRNA,IFN-γ mRNA of dendritic cells (DCs) after the 24 h interference of Mahuang Xixin Fuzi Decoction on DCs.Methods:The dendritic cells deriving from mouse bone marrow after 7 days culture in vitro were collected,then the DCs for 24 h were interfered with Mahuang Xixin Fuzi Decoction.The cells were collected and the contents of IL-4,IL-5 and IL-13 and the expressions of pSTAT6,IL-4 mRNA,STAT6 mRNA,GATA-3 mRNA were detected.Results:The contents of IL-4 (P<0.05) and IL-13 (P<0.01) was reduced after intervention of Mahuang Xixin Fuzi Decoction.There was no significant difference in content of IL-5 compared with the blank control group.The expressions of pSTAT6 decreased (P<0.01) and the expression of IL-4 mRNA,STAT6 mRNA,GATA-3 mRNA was decreased (P<0.01).Conclusion:Mahuang Xixin Fuzi Decoction could control the pathway of IL-4/STAT6 signal transduction and regulate the imbalance of Th1/Th2 and play a vital role in the treatment of allergic rhinitis.