Abstract： Objective To investigate the expression of intermedin (IMD) in plasma and tissues of lung cancer patients compared with control group and to explore the relationship of IMD with the stage and pathological type of lung cancer. Methods The content of IMD in plasma of 88 lung cancer patients measured using ELISA, 36 lung cancer tissue using immunohistochemistry, compared with control groups. Results Healthy control group IMD level [(38.68±12.65) pg/ml] was lower than lung cancer group [(81.61 ± 30.78) pg/ml] (t =-5.818, P <0.05); There was no significant difference of IMD between small cell [(68.61 ± 30.01) pg/ml] and non-small cell lung cancer [(75.51 ±32.74) pg/ml] (t =-0.680, P >0.05); IMD in stage Ⅳ is higher than stage Ⅰ - Ⅲ (t =-3.444, -3.093, -3.955, P <0.05); IMD with distant metastasis is significantly higher than that without distant metastasis (t =8.052, P =0.000). IMD expression in lung cancer tissues [23/36 (63.9 %)] is significantly higher than adjacent tumor tissues [5/21 (23.8 %)] (x2= 8.525, P <0.05). IMD in Stage Ⅲ[14/17(82.4 %)] is significantly higher than in stage Ⅰ [1/5 (20.0 %)] (x2 = 6.924, P =0.009). Conclusion The expression of IMD in lung cancer patients is significantly higher than control groups. Expression has correlation with stage and metastasis, which might play a vital role in the pathogenesis of lung cancer.