Sixty-one patients with primary lung cancer, who had CT and MR imaging before surgery, were studied. MR imaging used spin-echo sequences with T1 weighted image and T2 weighted image (C-MRI), and included STIR technique (Stir-MRI). The accuracy of diagnosis of mediastinal lymphadenopathy (regarding 10 mm or larger in short transverse diameter as positive) was 89% by CT, 84% by C-MRI and 89% by Stir-MRI. The accuracy of diagnosis of hilar lymphadenopathy was 42% by CT, 67% by C-MRI, and 75% by Stir-MRI. The accuracy of diagnosis of mediastinal lymph node metastases was 89% by CT, 94% by C-MRI and 96% by Stir-MRI. The accuracy of diagnosis of hilar lymph node metastases was 78% by CT, 87% by C-MRI and 89% by Stir-MRI. The possibility of enhancement of diagnostic accuracy of lymph node metastases from lung cancer was suggested by combining MR imaging included STIR technique with CT.