Cardiac hydatid cyst disease is uncommon, representing approximately 0.2% to 2% of all cyst-related cases. Cardiac hydatid cysts are found mostly within the myocardium. Most cardiac hydatid cysts are located in the interventricular septum or in the left ventricular wall. Only few cases of pericardial location have been reported; isolated pericardial hydatid cysts are especially extremely rare. Patients with a cardiac hydatid cyst are usually asymptomatic. We present the case of an asymptomatic patient with isolated pericardial hydatid cyst disease and discuss the role of chest X-rays in the incidental diagnosis of this condition.