DQ
DQ may stand for:

In arts and entertainment
Dragon Quest, a series of console role-playing games created by Enix (now Square Enix)
DragonQuest, a role-playing game created by SPI

Businesses
Dairy Queen, a fast food chain
Coastal Air Transport (IATA code DQ)

People
DQ (artist), Danish singer, participant in Eurovision Song Contest 2007
Dan Quayle, American politician
Dulquer Salmaan, Indian actor and singer
Dan Quinn (American football), football coach

In science and technology
HLA DQ, a human leukocyte antigen type protein
Data quality, various measures in information science
Design qualification, part of verification and validation
Digital Intelligence Quotient, a form of intelligence that combines knowledge in information technology and the socio-emotional ability to interact effectively through this medium
Double-ended queue, a data type in computer science

In sport
Disqualification (boxing)
Disqualification (professional wrestling)
Disqualification (tennis)

Other uses
DQ code, used in telephone directory assistance in the UK
Jarvis Island (FIPS PUB 10-4 territory code DQ)