Abstract: Objective: To investigate the lymph node metastasis of lung squamous cell carcinoma to provide the basis of dissecting lymph node.Methods: The clinical and pathological data of 251 cases with lung squamous cell carcinoma were statistically analyzed.Results: Among the dissecting 2 535 lymph nodes,metastasis occurred in 434 lymph nodes.The metastasis rates of lymph nodes in group 11,10,8,7,6,4 and 2 were high,the metastasis rates of lymph nodes in group 9,5,3 and 1 were low,the difference of which was statistically significant(P<0.01).The metastasis rate of lymph nodes in stage T1 patient was low.the metastasis rate of lymph nodes in patient with central lung cancer(50.5%) was higher than that in patient with peripheral lung cancer(27.1%)(P<0.01).The metastasis rate of lymph nodes of mediastinum in upper lobe lung squamous cell carcinoma was higher than that in lower(middle) lobe.The lymph node metastasis to superior mediastinum of primary lesion in upper lobe was more likely to occur,the lymph node metastasis to superior and inferior mediastinum of primary lesion in lower lobe was more likely to occur.The skip mediastinum metastasis rate was 19.5%.Conclusions: The lymph node metastasis of lung squamous cell carcinoma is closely related to primary lesion,which accompanied skip mediastinum metastasis.The lymph nodes of superior mediastinum and group 7 of inferior mediastinum should be dissected in patients with upper lobe primary lesion,the lymph nodes of superior and inferior mediastinum should be dissected in patients with lower(middle) lobe primary lesion.