Saint Mildgyth or Mildgytha (Old English: Mildgȳð; died 676) was the youngest daughter of Merewalh, king of Mercia and Saint Eormenburh. Her sisters were Saint Mildburh of Wenlock and Saint Mildrith. She was a Benedictine nun and later abbess of a Northumbrian convent. Her feast day is January 17.