Alfonso Jordan (French: Alphonse Jourdain; Latin: Ildefonsus) (1103–1148) is the Count of Tripoli (1105–09), Count of Rouergue (1109–48) and Count of Toulouse, Margrave of Provence and Duke of Narbonne (1112–48, as Alfonso I).

He is the son of Raymond IV of Toulouse by his third wife, Elvira of Castile.

He was born in the castle of Mont Pèlerin in Tripoli while his father was on the First Crusade.

He is given the name "Jordan" after being baptized in the Jordan River.