Objective:To indentify the expression of transcription factor GATA-3 and T-bet in asthmatic mice and observe the change of T-bet/GATA-3 balance interfered by dexamethasone. Methods:The BLAB/C mice asthma model was induced by classic method with ovalbumin; Twenty-four male mice were randomly divided into a control group, an asthmatic group and a dexamthasone(DEX)-treated asthmatic group in which mice were injected with dexamthasone(2 mg/kg) intraperitoneally. The pathological changes of lung were measured by HE staining, the expression of GATA-3 and T-bet mRNA of lung were measured by RT-PCR. The levels of IL-4 and IFN-γ in mice spleen CD4+T cell were measured by flow cytometry. Results:In the asthmatic group, the expression of GATA-3 mRNA and the level of IL-4 were significantly elevated compared to those in the control group(P < 0.05), the expression of T-bet mRNA and the level of IFN-γ were decreased compared to those in the control group(P < 0.05;P < 0.01). Both of GATA-3 and T-bet mRNA decreased after DEX treatment, and the decreasing degree of GATA-3 was more than that of T-bet. The expression of IL-4 and IFN-γ were depressed simultaneously and the downregulation of IL-4 was more than that of IFN-γ after DEX treatment. Conclusion:The imbalance of transcription factor GATA-3 and T-bet had a closely correlation with the airway inflammation in asthmatic mice. DEX could reverse the ration of IL-4/IFN-γ and regulate the balance of Th1 and Th2 through inhibiting both GATA-3 and T-bet.