Currently, previous studies have reported the effect of kaempferol against lung cancer in vitro, it can block TGF-β1-induced EMT and cancer cell migration by inhibiting Akt1-mediated phosphorylation of the Thr179 residue of Smad3 34.In our study, we first proved the therapeutic effect of kaempferol on xenograft lung cancer models in the in vivo experiment, and found that the volume and weight of tumors in mice treated with kaempferol were significantly reduced; and the results of pathological sections showed that the degree of malignancy was low. The gene discussed is SMAD3; the disease is lung cancer.