Sande, of Aberdeen, fought off competition from Adele, Dizzee Rascal, Noel Gallagher and Florence Welch to take home the prize for best solo artist.
It is just the latest highlight for the celebrated singer who carried the Olympic torch in Ballachulish in the Highlands, sang Abide with Me at the London Olympics opening ceremony in July and also performed at the event's closing extravaganza.
Django Django, formed at Edinburgh Art College where band members David Maclean, of Tayport, and Tommy Grace, of Edinburgh, met on a painting course, were awarded the title of best new act.
Britpop veterans Blur also saw off competition from fellow reformed rockers the Stone Roses to be named the best live act, while Muse were named best act in the world.
The awards also recognised dance duo Underworld, whose music provided much of the soundtrack to the Olympics opening ceremony, in the Q innovation in sound award.
Editor Andrew Harrison said: "It's been the most incredible year for British music. Our bands and our anthems transformed the Olympics.
"A string of great albums announced fantastic new talent on the scene. And amazing comeback shows from Blur and the Stone Roses showed the enduring appeal of our best-loved musicians.
"Q is proud to raise a glass to salute the artists that make Britain the world capital of rock and roll."
l Scottish fans of Muse will be able to see the band perform tomorrow night at Glasgow's SECC.
After picking up the best act in the world trophy, frontman Matt Bellamy said the band's success was something he had always dreamed of. He also said he was most proud of the fact he and his fellow band members had remained friends since forming.
Best new act: Django Django
Best track: Ill Manors, Plan B
Best album: The Bravest Man In The Universe, Bobby Womack
Best live act: Blur
Best video: Disconnected, Keane
Best solo artist: Emeli Sande
Best act in the world today: Muse
Q classic song: Walk On By, Dionne Warwick
Q spirit of independence: The Cribs
Q innovation in sound: Underworld
Q inspiration award: Pulp
Q icon award: Dexys
Q classic album: Generation Terrorists, Manic Street Preachers
Q hero: Johnny Marr
Q idol: Brandon Flowers