Agnes is a given name that can refer to:
- Agnes (20th century), a permanent patient at St Mungo's in the Janus Thickey Ward
- Agnes Monkleigh, a Slytherin student at Hogwarts in the 1990s
- Agnes Nutt, elderly witch living in Hogsmeade
- Agnes Scribner, librarian at Hogwarts School of Witchcraft and Wizardry in the late 19th century