Primary pericardial sarcomas are extremely rare. We report a case of 19 year old male who presented with cough,dyspnoea, and orthopnea. Investigations and exploratory thoracotomy revealed a large pericardial mass. Surgical debulking of the tumor was performed and the histopathological examination was compatible with synovial sarcoma. The tumor was unresectable due to its invasion and adhesion to mediastinal structures. Hence patient was started on palliative chemotherapy (adriamycin and ifosfamide based). Patient showed an initial symptomatic response but later on there was a clinical progression and died within six months of his diagnosis.