Nightmare
- Blwyddyn: 1964
- Gwlad: United Kingdom
- Genre: Thriller, Horror, Mystery
- Stiwdio: Hammer Film Productions
- Allweddair: dreams, nightmare, father murder, suicide attempt, asylum, girls' boarding school, psychological thriller, girls' school
- Cyfarwyddwr: Freddie Francis
- Cast: David Knight, Moira Redmond, Jennie Linden, Brenda Bruce, George A. Cooper, Irene Richmond