Irene Doukaina or Ducaena (Greek: Ειρήνη Δούκαινα, Eirēnē Doukaina) (c. 1066 – 19 February 1138) was the wife of the Byzantine emperor Alexios I Komnenos, and the mother of the emperor John II Komnenos and of the historian Anna Komnene.
Irene was born in 1066 to Andronikos Doukas and Maria of Bulgaria, granddaughter of Ivan Vladislav of Bulgaria. Andronikos was a nephew of Emperor Constantine X and a cousin of Michael VII.
Irene married Alexios in 1078, when she was still eleven years old. For this reason the Doukas family supported Alexios in 1081, when a struggle for the throne erupted after the abdication of Nikephoros III Botaneiates. Alexios' mother, Anna Dalassene, a lifelong enemy of the Doukas family, pressured her son to divorce the young Irene and marry Maria of Alania, the former wife of both Michael VII and Nikephoros III. Irene was in fact barred from the coronation ceremony, but the Doukas family convinced the Patriarch of Constantinople, Kosmas I, to crown her as well, which he did one week later. Anna Dalassene consented to this but forced Kosmas to resign immediately afterwards; he was succeeded by Eustratios Garidas.