〔Abstract〕 Objective To investigate the expression and therapeutic effects of miR-34a in mice with allergic rhinitis. Methods 10 mice were selected as blank control group, and 30 mice were used to construct mouse allergic rhinitis model with ovalbumin. They were randomly divided into model group, miR-34a inhibitor group and negative control group(NC group) with 10 cases each. 100 μl of physiological saline, 100 μl of negative transfection plasmid, and 100 μl of miR-34a inhibitor carrier mixed solution were injected into the tail vein respectively. The behavioral changes of mice after 1 week of intervention were observed; ELISA was used to detect the level of ovalbumin-specific IgE in mouse serum; qRT-PCR was used to detect interleukin(IL)-6, IL-8, IL-10, and IL-35, the relative expression of matrix metalloproteinase(MMP)-2, MMP-9 and vascular cell adhesion molecule(VCAM)-1 mRNA. The content of CD3+, CD4+, CD8+T cells in peripheral blood was detected by flow cytometry.Results The serum level of miR-34a mRNA in model mice was significantly higher than that in the blank group(P<0.05). Compared with the negative control group, the total behavioral score of mice after miR-34a inhibitor intervention was significantly reduced(P<0.05). The concentration of ovalbumin-specific IgE was significantly reduced(P<0.05), while IL-6, IL-8, IL-10, MMP-2, MMP-9 and VCAM-1 mRNA were significantly reduced(P<0.05), IL-35 increased significantly(P<0.05), and CD3+, CD4+/CD8+increased significantly(P<0.05). Compared with the blank control group, the levels of IL-2 and IFN-γ in the model group decreased(P<0.05); compared with the model group, the levels of IL-2 and IFN-γ in the miR-34a inhibitor group and NC group increased(P<0.05); those indexes of miR-34a inhibitor group and NC group were compared,and there were statistically significant differences(P<0.05); there was no difference between the model group and NC group.Conclusion miR-34a is highly expressed in mice with allergic rhinitis. Inhibition of miR-34a expression can significantly reduce the symptoms and inflammation of model mice, and improve immune function.