We report a case of an elderly male whose pulmonary reaction with skin eruption occurred in the initial phase of chemotherapy composed of isoniazid, rifampicin, and ethambutol (EB). A peripheral lymphocyte stimulation test (LST) showed a positive reaction only to EB. The blood serum analysis of the patient when this reaction occurred revealed an elevated titer of antinuclear antibody. Computed tomography (CT) scan films of the chest when the pulmonary reaction occurred showed multifocal subpleural consolidations. There has been only one reported case of EB-induced pulmonary reaction and its clinical course was very similar to ours. However, LST results and computed tomography (CT) scan findings of the chest were not documented in that case.