Odo ( or Odon, ; c. 1010 – 10 March 1039) was Duke of Gascony from 1032 and then Duke of Aquitaine and Count of Poitou from 1038. He was a member of the House of Poitiers, the second son of William V of Aquitaine, the eldest by second wife Sancha of Gascony, daughter of William II of Gascony and sister of Sancho VI.