Objective To study the p-mammalian target of rapamyein(p-roTOR)expression and its prognostic significance in non-small cell lung cancer(NSCLC).Methods Immunohistochemical staining of EnVision was applied to investigate the expression of p-roTOR in lung specimens from 59 cases with NSCLC and 10 cases with benign pulmonary diseases(3 pulmonary tuberculosises and 7 inflammatory pseudotumors 1.Results The positive rate of p-mTOR was 40.7% in NSCLC which was significantly higher than that in the benign pulmonary diseases(x =6.237,P=0.013).The expression of p-mTOR was closely correlated with age,sex and pTNM stage.Kaplan-Meire survival analysis revealed that the expression of p-mTOR was not correlated significantly with survival days(Log rank test P =0.055).Conclusion P-mTOR might be a biomark for differential diagnosis of malignant lung disease,but has poor prognostic value.