Joseph Timothy O'Callahan was a Jesuit priest and, during World War II, a United States Navy chaplain. He was awarded the U.S. military's highest decoration, the Medal of Honor, for his actions during and after an attack on the aircraft carrier aboard which he was serving, USS Franklin.

USS O'Callahan (FF-1051) was a U.S. Navy Garcia-class destroyer escort, later reclassified as a frigate. She was named for Chaplain Lieutenant Commander Joseph T. O'Callahan, a World War II Medal of Honor recipient for his rescue of crewmen on the aircraft carrier Franklin after it was hit and severely damaged by enemy bombs.