A fractured femur of a giant fossil penguin from the Anthropornis nordenskjoeldi Biozone (Late Eocene), Isla Marambio (Seymour Island), Antarctica (La Meseta Formation) is described. Palaeoecological, palaeopathological and taphonomical implications derived from the analysis of the kinds of fractures identified are also discussed. The main fracture has irregular margins, indicating there was collagen in the bone at the time of the impact. In this fracture, a mineral deposit was also identified as a fracture hematoma. According to the antemortem classification of fractures, it was produced by an indirect mechanism, provocating a “butterfly wing” or “third fragment” fracture. The remaining fractures are assigned to times of biostratinomic and fossil diagenesis.