To investigate the effect of formononetin on the proliferation and apoptosis of glioma cells and its molecular mechanism.Methods:A subcutaneous xenograft tumor mouse model was established，and mice were orally administered with formononetin at 5.72，14.31，22.9，and 31.49 mg/kg.Tumor weight and volume changes were observed，and the expression of proliferating cell nuclear antigen(PCNA) in tumor tissues was detected using immunohistochemistry.TJ905 cells were treated with different concentrations(20，50，80，and 110 μmol/L) of formononetin，and the cells were divided into blank control group，110 μmol/L formononetin group，110 μmol/L formononetin+miR-1229 group，110 μmol/L formononetin+miR-1229+ZDHHC9 group，miR-NC group，and miR-1229 mimic group.Cell proliferation ability was detected using Edu assay and CCK-8 assay.Cell apoptosis was detected using TUNEL assay.The expression levels of miR-1229 and ZDHHC9 mRNA were measured using real-time fluorescence quantitative polymerase chain reaction(RT-qPCR) assay.The targeting binding of miR-1229 to ZDHHC9 was verified using online websites and dual luciferase reporter gene assay.Results:Compared with the blank control group，the tumor volume，weight，and PCNA protein expression in the formononetin-treated groups at different doses were significantly reduced(all P<0.05).Compared with the control group，treatment with different concentrations(20，50，80，and 110 μmol/L) of formononetin significantly reduced cell proliferation rate and increased apoptosis rate(all P<0.05).Compared with the 110 μmol/L formononetin group，the cell proliferation rate and viability in the 110 μmol/L formononetin+miR-1229 group were significantly reduced，and the apoptosis rate was significantly increased(all P<0.05).Compared with the 110 μmol/L formononetin+miR-1229 group，the cell proliferation rate and viability in the 110 μmol/L formononetin+miR-1229+ZDHHC9 group were significantly increased，and the apoptosis rate was significantly decreased(all P<0.05).The dual luciferase reporter gene assay confirmed the targeted binding of miR-1229 to ZDHHC9.Conclusion:Formononetin may inhibit the proliferation of glioma cells and induce their apoptosis through the miR-1229/ZDHHC9 molecular axis.