A 22-year-old woman was admitted to our hospital complaining of productive cough and dyspnea even at rest, and marked cervical lymphadenopathy. Marked stridor and orthopnea were observed, and auscultation of the chest revealed widespread expiratory wheeze which was not relieved by bronchodilators administered intravenously. Chest X-ray and CT scan revealed hilar lymphadenopathy and invasive tumor of the mediastinum. Bronchoscopy demonstrated narrowing of the trachea anteriorly and posteriorly and a submucosal nodular tumor protruding from the right anterior wall, causing approximately 90% occlusion of the lumen of the lower third of the trachea, but distal bronchi were intact. Microscopic findings of inguinal lymph node biopsy specimen revealed mixed cellular lymphoma compatible with Hodgkin's disease. Systemic chemotherapy resulted in relief of symptoms, and two months later, the endotracheal tumor had disappeared bronchoscopically, with slight residual stenosis of the trachea. Before treatment, pulmonary function tests indicated markedly impaired forced volume in 1 second in both expiratory and inspiratory cycles, especially in the latter phase. After remission, however, obstructive ventilatory dysfunction was observed. The cause of prolonged air flow obstruction was thought to be marked infiltration and almost total involvement of the tracheal wall by tumor with a nodular appearance of the lumen. Endotracheal tumor in Hodgkin's disease is rare, and there are few reports on pulmonary function associated with intrathoracic involvement of malignant lymphoma.