Objective:To investigate the characteristics of lymph nodes metastasis in T1 non-small cell lung cancer(NSCLC).Methods:The clinical data of 276 cases underwent resection of NSCLC from January 2011 to November 2012 were analyzed retrospectively. Characteristics of tumors,lymph nodes involvement were analyzed in those cases. Results:①In all 276 cases,66 cases were confirmed pathology with lymph node metastasis,metastasis rate was 23.9%(66/276). The metastatic rates in group of well differentiated and poorly differentiated were 6.1% and 33.7% respectively,the difference being significant(P < 0.05). ② The frequency of metastasis was higher in patients with a primary tumor in the right middle lobe compared to the right upper and left lower lobe(χ2 = 5.545,P < 0.05 and χ2 = 5.402,P < 0.05). Conclusion:In T1 NSCLC,lymph nodes metastatic rate is closely related with the degree of tumor differentiation. The frequency of metastasis was higher in patients with a primary tumor in the right middle lobe. It is necessary to perform systematic node dissection during pulmonary resection for those patients.