Primary lung sarcomas are rare but aggressive tumors accounting for less than 0.5% of all lung tumors. The diagnosis of primary lung sarcoma should only be considered after exclusion of other sites. A 32-year-old female presented with recurrent hemorrhagic pleural effusions, shortness of breath and persistent cough. Pleural effusion was drained twice, and each time its analysis was normal. Patient developed atelectasis of left lung with hemothorax for which she underwent video-assisted thoracoscopic surgery. A large mass was found compressing the entire lower lobe of left lung with extension into mediastinum, the biopsy of which showed myxoid sarcoma. The tumor was inoperable and options of chemotherapy or radiotherapy were discussed with the patient. Primary lung sarcoma can rarely present with recurrent hemorrhagic pleural effusion. A high degree of suspicion is required for early diagnosis as large hemothorax on computed tomography or chest X-ray may obscure lung mass and make its diagnosis difficult.