5H

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)
 * 5Hydrogen, a highly unstable isotope of hydrogen
 * City of Death (production code: 5H), a 1979 Doctor Who serial