We report a rare case of giant cell tumor (GCT) of the sternum in a 55-year-old man. He presented with a bony mass in the body of the sternum that had been slowly growing over 6 months. The patient was treated by surgical curettage and cementation. Histological study showed typical GCT findings with cytogenetic abnormalities of many telomeric associations of chromosomes, predominantly the 19q arm.