From January 1981 through December 1989, 15 patients with small advanced lung cancer were treated surgically at the Tenri Hospital. In these cases, the diameter of peripheral lung cancer did not exceed 3.0 cm (T1) and mediastinal lymph nodes were proved to be N2 postoperatively by lymph node dissection or sampling. The histological types were as follows: 8 adenocarcinoma, 4 large cell carcinoma, 1 squamous cell carcinoma, 1 small cell carcinoma, and 1 adenosquamous carcinoma. All but one patient were received postoperative chemotherapy and/or radiotherapy. The survival rate was 44.5% at 3 years, and median survival time was 36 months. The mediastinal lymph node metastasis with small peripheral lung cancer (T1N2) was ominous, and it should be said that complete mediastinal lymph node dissection and adjuvant therapy were indispensable to small advanced adenocarcinoma of lung.