A 74-year-old man was admitted to our hospital because of an abnormal shadow in the left middle lung field on chest radiography. Since a transbronchial biopsy was not diagnostic, a left lower lobectomy was performed. Histopathologically, the patient was diagnosed as having an inflammatory pseudotumor of the lung. Four months after the surgery, the patient was readmitted with hemosputum. Bronchoscopically, an endobronchial lesion was found in the left main bronchus. Transbronchial biopsy of the lesion showed proliferation of inflammatory cells compatible with inflammatory pseudotumor. Therefore, a recurrent inflammatory pseudotumor was diagnosed. Treatment with corticosteroid resulted in the disappearance of the endobronchial lesion and the erythrocyte sedimentation rate (ESR) returned to normal. The patient showed a prolonged elevation of ESR even after the resection, suggesting that the ESR may be a good indicator of the activity of this disease.