A 57-year-old male presented with hemoptysis of 4 years duration and a gradually increasing pleural mass on chest X-ray. The mass was causing pressure effects on the liver and the lungs. To rule out malignancy, thoracotomy was performed, which revealed large, thick-walled hematoma. Complete excision of mass was performed. Post-operative course was complicated by massive pleural bleeding requiring massive blood transfusions and re-exploratory thoracotomy. Subsequent tests revealed factor IX deficiency and, hence, he was managed with recombinant factor IX concentrate. This case stresses upon the fact that hereditary bleeding disorders may be diagnosed even in late adulthood with atypical presentations such as pseudotumor in pleural space. Moreover, hemophilia B may present with normal APTT levels making the diagnosis even more difficult.