CQ can stand for several different things:

• CQ is a code used by wireless telegraphy and voice operators to make a general call, invitating other operators listening on that channel to respond.
• CQ is the abbreviated title of Congressional Quarterly a publication that summarizes the legislative activities of the United States Congress.
• CQ (2001) is a film directed by Roman Coppola and starring Jeremy Davies and Angela Lindvall .
• CQ is also used to refer to Central Queensland, an area in Queensland, Australia
• CQ is a notation used in copyediting that stands for correct if queer, to signify that an unusual-looking spelling or word usage has been double-checked. Sometimes QC (queer but correct) is used.