Bauer [then Emap] launched Q TV in October 2000, operated by Box Television, and specialising in indie, rock and alternative.
The closure makes way for Heat TV, which is set to launch on 3 July with a selection of music videos, news stories and links to social networks.
Heat TV joins Bauer-branded channels Kiss, Kerrang!, Magic and Smash Hits, which are managed by Box TV, a joint venture between Bauer Media and Channel 4. Box TV's stable also includes 4Music and The Box.
Heat TV, which will broadcast on Sky and Virgin Media, is also likely to be available in Ireland on UPC Ireland and in Iceland on Síminn.
At the time of the launch of Q TV the circulation of the monthly music magazine, which was launched in 1986, averaged 204,014 copies.
It had dropped to 113,174 copies at the time of the launch of Q Radio in the first half of 2008 and the most recent ABC figures, for July - December 2011, show it is currently at 77,522 copies.
A Bauer Media spokeswoman said the closure of the TV channel would have "no impact on the magazine".
She added: "The magazine has a number of exciting plans for the coming months under the editorship of Andrew Harrison and we’re currently exploring how the Q brand can offer the consumer the best possible iPad experience.
"The Q awards remain an important brand extension for the magazine and last year’s event formed a unique and unforgettable part of the Q25 anniversary celebrations with attendees including U2, Coldplay, Noel Gallagher and Gary Barlow."
Heat magazine, which launched in 1999, has already given rise to a radio station and currently has an average weekly circulation of 325,370 copies.
Lucie Cave, editor of the magazine, said: "The heat brand has defined celebrity culture for over ten years in print, online and on the radio. We've amused, delighted and, yes, enlightened 'the heat generation' in every way but one: TV. So now we're taking that over too with a 24/7 mix of celeb news as it happens, amazing music, unparalleled access and entertainment."