5H or 5h may refer to:
- Fifth Harmony, the American girl group
- 5H, a type of lead in a pencil
- SSH 5H (WA), alternate designation for Washington State Route 507
- Fly540 (IATA code)
- 5
H
, a highly unstable isotope of hydrogen - City of Death (production code: 5H), a 1979 Doctor Who serial