Hibernomas are rare heterogeneous fatty tumors arising from brown fat precursors. Intrathoracic hibernomas are extremely rare. We detail a case of pathologically proven intrathoracic hibernoma in a 67-year-old woman. Chest radiography, computed tomography, fluorodeoxyglucose positron emission tomography, and angiography are presented. A short review of the literature and discussion of imaging and histologic diagnosis of hibernomas are provided.