Sword fern is a common name for several ferns and may refer to:
- Nephrolepis, a tropical genus of ferns, especially:
- Nephrolepis exaltata, commonly cultivated as a houseplant, including the Boston fern
- Polystichum, a cosmopolitan genus of ferns, especially:
- Polystichum munitum, native to western North America
- Giant swordfern