Her hit song Next To Me was named best song musically and lyrically, and also won the prize for most performed work.
Other winners at Thursday’s ceremony in London included Noel Gallagher, Marc Almond, Justin Hayward and Randy Newman.
The annual awards, in their 58th year, celebrate songwriting and composing and are voted for by songwriters.
Sande, who was not present to pick up her awards at the Grosvenor House hotel, performed at the London 2012 opening and closing ceremonies.
Last month her album Our Version of Events beat a record set by The Beatles for the most consecutive weeks spent in the UK’s Top 10 by a debut album.
Calvin Harris, named songwriter of the year, called his accolade “easily the greatest achievement of my entire life”.
“I can’t believe I was even let in the door of this whole ceremony,” he said. “It feels like I shouldn’t be here.”
The DJ and producer made chart history last month by becoming the first artist to have eight Top 10 hits from one studio album, 18 Months.
Gallagher, who collected the award for outstanding song collection from The Kinks’ Ray Davies, said: “I’d like to thank anyone who’s ever played on any of my songs.”
Clutching his award backstage, the former Oasis star said: “I’ve got three kids, and if they ever show any interest in songwriting, I can pop that down on the table in front of them and say ‘give it your best shot’.”
The first award of the day – for best contemporary song – went to Pelican by The Maccabees.
Mercury Prize winners Alt-J won the award for best album with An Awesome Wave.
Almond, who was launched to fame by Soft Cell before enjoying a solo career, was given the inspiration award.
Moody Blues star Justin Hayward won the outstanding achievement prize, while US singer-songwriter Randy Newman – whose movie soundtracks include Toy Story – was given the international award.
By Tim Masters
Entertainment and arts correspondent, BBC News