Although pericardial cysts are generally benign structures and detected incidentally, they may be associated with life-threatening complications. We present the case of a 24 year-old man with a giant hemorrhagic pericardial cyst diagnosed after evaluation for recurrent syncope which caused compression of the right ventricle. Spontaneous hemorrhage into a pericardial cyst is an extremely rare event, and to our knowledge this is the first case in which a pericardial cyst has been shown to cause recurrent syncope.