Cardiac hydatidosis is a rare condition, particularly when the cyst is localised in the interventricular septum. We describe this unusual presentation of echinococcosis in a 21-year-old man, who was admitted with chest pain, dyspnea and a history of two episodes of fever with chills and rigors. Echocardiographic evaluation revealed a cystic mass with multiple loculations in the interventricular septum of the heart, extending into posterior left ventricular wall. Magnetic resonance imaging showed a hypointense cyst in the interventricular septum. The haemogram showed an eosinophil count of 24%. The patient underwent surgery. The hydatid fluid was drained, daughter cysts and hydatid sand removed, and the cyst cavity was closed after instillation of 20% hypertonic saline. On gross examination of the material, glistening, multiple pieces of cystic membrane were seen. Microscopic examination showed acellular chitinous, laminated membranes, granular germinal layer and few degenerated brood capsules and protoscoleces.  Post operatively, an echocardiogram showed a sclerosed cyst cavity. There was no septal defect and the patient was asymptomatic when discharged.