Thomas FitzThomas FitzGerald, 3rd Baron of Desmond (c. 1290 - 1307), succeeded to the barony of Desmond, which lay in Munster, in the south of Ireland, in 1296, at the age of six, upon the death of his father, Thomas FitzGerald, 2nd Baron Desmond. Thomas died young while still unmarried and childless, and was succeeded by his brother, Maurice FitzThomas FitzGerald.