Pumonary catheterization and angiography were done for diagnosis. Chest radiographs of total occlusion cases showed decreased lung volume, features of pulmonary edema, interstitial lesions, and pleural thickening, which were quite specific, whereas pulmonry venous dilatation was dominant findings in partial obstruction cases. Pulmonary perfusion scans (n=3) showed total perfusion defects in the cases of total occlusion of veins. MR imaging (n=2) demonstrated total occlusion of pulmonary veins in the venoatrial junction in two, and membranous focal obstruction in one lung. Two patients had pneumonectomy and histological confirmation, Although catheterization and angiography are essential for the diagnosis, MR imaging is thought to be useful for the diagnosis of pulmonary vein obstruction.