Abstract: To study the immunomodulatory effect of hawthorn flavonoids on spleen lymphocytes in mice,mice were divided into blank group,levamisole group and hawthorn flavonoids treatment group(100,200,400 and 800 μg/mL). MTT method was used to detect the effect of hawthorn flavonoids on lymphocyte proliferation. ELISA method was used to detect the effect of hawthorn flavonoids on lymphocyte interleukin-6(IL-6),interleukin-4(IL-4),interferon-γ(IFN-γ). Flow cytometry was used to detect the effect of hawthorn flavonoids on lymphocyte membrane surface markers(CD4⁺ and CD8⁺). Results showed that hawthorn flavonoids had concentration dependence on lymphocyte proliferation and lymphocyte factor secretion ranged from 100 to 400 μg/mL. The secretion of IL-6 and IFN-γ were higher than that of the blank group extremely significant(P<0.01),and the secretion of IL-4 was lower than that of the blank group extremely significant(P<0.01),and there was no statistical significance between the 400 μg/mL treatment group and levamisole group(P>0.05). The percentage of CD4⁺ CD8^- and CD4^- CD8⁺ in lymphocyte subsets had a centration-dependent promoting effect,which was higher than that in blank group and levamisole group extremely significant(P<0.01). The percentage of CD4⁺/CD8⁺ in lymphocyte subsets was higher than that in blank group and levamisole group extremely significant(P<0.01),and the ratio of CD4⁺/CD8⁺ in 200 μg/mL treatment group was higher than that in other concentration groups(P<0.01). Hawthorn flavone could enhance the CD4⁺/CD8⁺ ratio of lymphocyte subpopulation by inducing lymphocyte proliferation and secretion of lymphocyte factors IL-6,IL-4 and IFN-γ ranged from 100 to 400 μg/mL,and it played an immunomodulatory role.