6H or 6-H can refer to:

IATA code for Israir Airlines Curtiss JN-6H JN-6H Jenny; see Curtiss JN-4 Isuzu 6H Engine 6H-SiC, one of the Polymorphs of silicon carbide Hydrogen-6 (6H), an isotope of hydrogen 6H, the production code for the 1983 Doctor Who serial Enlightenment

See also H6 (disambiguation)