6J or 6-J can refer to:
IATA code for Solaseed Air (Ex Skynet Asia Airways) 6-j symbol 6J, a model of SEAT Ibiza Hughes MH-6J, model of Hughes OH-6 Cayuse AH-6J, a model of MD Helicopters MH-6 Little Bird AS.6J, a model of Airspeed Envoy 6J, designator for Clatskanie School District 6J6, see List of caves in Western Australia WS-6J, engine model in Xian H-6 CA-6J, a model of Buhl Airsedan RE-6J, or Burlington Public School District; see Table of Colorado school districts T-6J, one of the North American T-6 Texan variants 6J, the production code for the 1983 Doctor Who serial The King's Demons
See also J6 (disambiguation)