6U
6U  or 6-U may refer to:

Aviation 
 Air Ukraine (IATA code:6U)
PW-6U, a model of Politechnika Warszawska PW-6 glider
HY-6U, a model of Xian H-6 jet bomber

Other technologies 
 6U, a rack unit configuration of 10½-inch depth
RG-6/U coaxial electrical cable
6U, a model of Zenit Soviet spy satellite

See also
U6 (disambiguation)