Thoracic splenosis is a rare occurrence that has usually been diagnosed by invasive procedures to allow a pathologic diagnosis to be reached. A firm diagnosis can now be made with the help of new, noninvasive imaging techniques. We report the case of a 34-year-old man with a history of severe thoracic-abdominal injury, including rupture of the spleen and left diaphragm. During computed tomography of the thorax related to a different diagnosis, nonspecific nodules were observed, although the patient was asymptomatic. A suspected diagnosis of thoracic splenosis was confirmed by technetium-99 sulfur colloid scintigraphy.