Pericardial cysts are benign intrathoracic lesions typically located at the right costophrenic angle (70%) or the left cardiophrenic angle (10 to 40%) and occasionally along the upper mediastinum, hilus, or left cardiac border. Usually pericardial cysts do not cause symptoms and constitute an occasional finding. However, occasional episodes of dyspnea, tachycardia or arrhythmias, sometimes cause intermittent retrosternal discomfort extending to the left arm. Two dimensional echocardiography may be used for accurate diagnosis of pericardial cysts and may obviate the need for more extensive investigation. For its high sensitivity and ability to differentiate solid from cystic masses and to define their relationship with cardiac chambers, this technique remains a reliable method for assessing pericardial cysts, giving to the clinician useful information for surgical decisions, or for other clinical investigations. We report the two dimensional echocardiographic findings in a 77-year-old man with voluminous pericardial cyst. We believe that this technique may be a simple, non invasive means of diagnosing these pericardial lesions.