Hydatidosis is a cosmopolitan pathology quite frequent in Tunisia. The cardio pericardial localization is a rare and formidable pathological entity because of its complications. In this book we have dealt with the different diagnostic and therapeutic modalities related to cardio pericardial hydatid cyst. Cardio-pericardial hydatidosis is a serious complication that must be diagnosed in time to avoid complications. The treatment is essentially surgical associated with medical treatment to avoid the dissemination of scolex.