Pericardial effusion can either be an incidental finding or a manifestation of systemic or cardiac disease. It has a wide range of presentations, from asymptomatic small effusion to rapidly progressive fatal tamponade. In a trauma setting, pericardial effusion is usually attributed to hematoma collection, with the concern of clinical evidence of tamponade that can lead to cardiopulmonary collapse. The Focused Assessment with Sonography for Trauma (FAST) is a widely used tool to diagnose pericardial effusion in trauma patients. We published this case report to emphasize that the presence of pericardial effusion alone in a trauma patient does not indicate the presence of tamponade. This case concerns a 39 years old male patient who presented to ER as a trauma case after a fall from two meters height and landing on his feet. ATLS protocol was followed, and FAST showed an incidental finding of massive pericardial fluid. The trauma team was consulted, and the patient was hemodynamically stable without clinical evidence of tamponade. Echocardiography showed mitral valve stenosis and large pericardial effusion. The close observation did not suggest the presence of cardiac tamponade. The pericardial catheter was inserted during admission with drainage of 900cc of serous fluid. The presence of pericardial fluid in a trauma setting does not confirm the diagnosis of tamponade. The mechanism of injury, clinical presentation, and the patient's stability are essential factors in determining further management of such patients.