The pericardium is an uncommon site for manifestation of pheochromocytoma. Herein, the case of a 57-year-old man with cardiac tamponade is presented. Pericardiocentesis was performed, and the vital signs were stabilized afterwards. An abdominal computed tomography (CT) scan illustrated a nonhomogeneous right adrenal mass suspicious of pheochromocytoma, planned for right adrenalectomy. He recovered well after surgery, and his subsequent follow-ups did not reveal any complications. [ABSTRACT FROM AUTHOR]