Fernando Ansúrez I was the Count of Castile in 929 and the earliest known member of the Beni Ansúrez family; his father, Ansur, is known only through his patronymic. He was also count of the Tierra de Campos, which was later formed into the County of Monzón for his son.
- Position held
- Count of Castile, Count of Burgos, Count of Castile
- Born
- 900
- Died
- 929
