Wulfthryth (fl. 868) was a queen of Wessex, the wife of King Æthelred I.
Little is known of Wulfthryth. She witnessed a charter of 868, in which she has the title of regina ("queen"). The charter appears in the Codex Wintoniensis, but Wulfthryth is otherwise unrecorded in primary sources. Stephanie Hollis notes that 868 was the year of Alfred the Great's marriage to a Mercian and that "Wulfthryth's name looks Mercian". Wulfthryth may be related to the Ealdorman Wulfhere who was granted land in Wiltshire by King Æthelred I in 869 and had his land confiscated for treason by King Alfred He is identified incorrectly as "Wulfhere princeps" in the 869 charter and his name appears directly below that of "Wulthryth regina".
