GRU may mean:
Glavnoye Razvedyvatelnoye Upravleniye (???, Russian for "Main Intelligence Directorate"), a Russian military intelligence organization (extant since 1918)
Gru, a Serbian hip-hop artist
Guarulhos International Airport, in the city of São Paulo, Brazil (IATA airport code)
Gainesville Regional Utilities, a power and utility company in Gainesville, Florida
Gru may mean:
Grus , standard astronomical abbreviation
GRUGRUGRU GRU