Her parents were John I Doukas of Thessaly and his wife Hypomone (a daughter of the Thessalian Vlach chieftain Taronas). In ca. 1273/76, Helena married Serbian king Stefan Milutin (r. 1282–1321), but Milutin abandoned her in ca. 1283. It is possible that their sons were Kings Stefan Konstantin and Stefan Dečanski. It seems Helena then returned to Greece.
- Polemis, Demetrios I. (1968). The Doukai: A Contribution to Byzantine Prosopography. London: The Athlone Press.CS1 maint: ref=harv (link)
- Trapp, Erich; Beyer, Hans-Veit; Walther, Rainer; Sturm-Schnabl, Katja; Kislinger, Ewald; Leontiadis, Ioannis; Kaplaneres, Sokrates (1976–1996). Prosopographisches Lexikon der Palaiologenzeit (in German). Vienna: Verlag der Österreichischen Akademie der Wissenschaften. ISBN 3-7001-3003-1.