To investigate the effect of Panax japonicus saponin on brain nerve injury，microvascular density(MVD) and TNF-1β in lung cancer rats by regulation of NF-κB signaling pathway.Methods:Forty SPF male SD rats were randomly divided into normal group(A)，model group(B)，Atractylodes atractylodes polysaccharide(C) group and P.japonicus saponin(D) group，with 10 in each group.Lung cancer modeling was performed in groups B，C and D by endobronchial perfusion of carcinogenic iodide oil.After successful modelling，group C was intragastrically administered with 80 mg/kg A.atractylodes polysaccharide; group D was intragastrically administered with 40 mg/kg P.japonicus saponin; groups A and B were given the same volume of normal saline by gavage.HE staining was used to observe the pathological morphology of lung tissue，and TUNEL assay was performed to detect brain nerve injury.ELISA was performed to detect the serum TNF-β of rats.MVD in lung tissue was determined by immunohistochemistry，and NF-κB protein expression in lung tissue was measured by Western blot.Results:Lung tissue and alveoli were normal and intact in group A，while obvious pathological changes were seen in group B.Compared with the condition in group B，the pathological structure in groups C and D was significantly improved，and group D was better than group C.Compared with group A，group B had increased hippocampal cell apoptosis，MVD，and NF-κB protein expression(P<0.05)，and decreased serum TNF-β(P<0.05).Hippocampal cell apoptosis，MVD，NF-κB protein expression and tumor volume in groups C and D were lower than those in group B(P<0.05)，while the serum TNF-β was higher(P<0.05)，with group D having more obvious changes than group C(P<0.05).Conclusion:P.japonicus saponins may significantly improve brain nerve injury and MVD by negatively regulating NF-κB signaling pathway and increasing TNF-β in rats.