Objective To investigate the expression of adrenomedullin (ADM) and vascular endothelial growth factor( VEGF) in plasm of patients with lung cancer,their correlation,and clinical significance. To explore the potential value of ADM for lung cancer in clinic. Methods The levels of plasms ADM and VECF were measured by means of radioimmunoassay in 66 cases of lung cancer, 31 cases of benign lung disease and 16 cases of healthy persons.Results The expression levels of plasm ADM and VEGF were significantly higher in the patients with lung caner than those in benign lung disease and healthy persons (P <0.05) , ADM in benign lung disease was significantly higher than that in the healthy persons (P <0.05), while VEGF in benign lung disease and healthy persons had no significant difference (P >0.05). The levels of plasm ADM and VEGF in distant metastasis was significantly higher than those with local lymph node metastasis ( P < 0.05 ) ,local lymph node metastasis was significantly higher than those without lymph node metastasis (P <0. 05). The levels of plasm ADM and VEGF were closely related to the local lymph node metastasis, distant metastasis and TNM staging. Furthermore, the expression levels of plasm ADM and VEGF increase with the clinical stage (P < 0.05 ). There was a significantly positive correlation between ADM and VEGF in patients with lung cancer (r = 0.449, P < 0.01) , but there was any correlation between benign lung disease group and healthy group ( P > 0. 05 ). Conclusion ADM and VEGF have synergistic effects in the process of neovascularization in lung cancer; to detect the expression of ADM, VEGF in plasm may be helpful for diagnosis of lung cancer and benign lung, lung cancer clinical staging,to interfere with ADM and its signal transduction pathway may be another new targeted therapy of lung cancer .