Abstract: Objective:To study the value of Video-Mediastinoscopy (VM) in preoperative staging of lung cancer.Methods: Forty patients underwent VM through cervical or (and) anterior mediastinum parasternal approach. Among the 40, 36 had mediastinal lymphnodes smaller than 1 cm and were pathologically diagnosed with lung cancer. The other 4 patients were highly suspected with lung cancer clinically. Results: VM showed that28patients had no involvement in the mediasti-nal lymph nodes and all of them underwent thoracotomy and lobectomy, with dissection of the mediastinal lymph nodes. The postoperative pathologic diagnosis showed that there were no cancer cell infiltration, consistent with the results of VM. Twelve cases were found with positive lymphnodes and surgical treatment was not considered. Among these12patients, 10were of N2 and received neoadjuvant chemotherapy, 2 were of N3 and received chemotherapy or radiation therapy. The average duration of VM surgery was 62minutes and the mean blood loss was50mL. No infection of incision was seen. The rate of complication was 2.5% (1/40) and no death occurred. The sensitivity and specificity of VM in staging mediasti-nal lymph nodes of lung cancer preoperatively were 100 %.Conclusion:Video Mediastinoscopy is a useful surgical proce-dure for the diagnosis and staging of lung cancer, with high diagnostic rate and less trauma.