9U

9U or 9-U may refer to:

Transportation

 * Air Moldova (former IATA code: 9U), a former airline
 * Yak-9U, a model of Yakovlev Yak-9
 * Su-9U, a designation of Sukhoi Su-9
 * 9U, a type of Volkswagen Caddy
 * Burundi (aircraft registration code: 9U)

Computing

 * 9U, one of the possible sizes of a rack unit
 * HP 9U, a Windows 3.0 version of the Windows-1252 codepage by Hewlett-Packard printers