Plan B won both of the awards he was nominated for, which included 'PRS for Music Most Performed Work' and the 'Album Award', as well as 'Songwriter Of The Year'.
The star, real name Benjamin Drew, was presented with the latter prize from Elton John and said: "I just want to promise to the world that I am never going to put out music that I don't like."
Tinie Tempah picked up his first Ivor for 'Best Contemporary Song', and also took up presenting duties by handing the 'Inspiration Award' to fellow rapper Dizzee Rascal.
The annual ceremony celebrates excellence in music writing and recognises talent from composers across all genres.
A complete list of the winners is as follows:
Best Song Musically and Lyrically
Villagers, 'Becoming a Jackal', written by O'Brien, published by Domino Publishing Company
Best Contemporary Song
Tinie Tempah, 'Pass Out', written by McKenzie, Okogwu and Williams, published by EMI / Stellar Songs Ltd
Plan B, The Defamation of Strickland Banks, written by Benjamin Drew, published by Universal
PRS for Music Most Performed Work
Plan B, 'She Said', written by Appapoulay, Cassell, Drew and Wright-Goss, published by Sony / ATV / Universal
Best Television Soundtrack
Any Human Heart, composed by Dan Jones, published by Faber / Universal
Best Original Film Score
How To Train Your Dragon, composed by John Powell, published by BMG Chrysalis
Best Original Video Game Score
Napoleon: Total War, composed by Beddow, Birdsall and Livingstone, developed by The Creative Assembly, published by SEGA
Classical Music Award
PRS for Music Outstanding Contribution to British Music
Songwriter Of The Year Award
Watch the video for Plan B's 'She Said' below:
Watch the video for Tinie Tempah's 'Pass Out' below:
Watch the video for Villagers' 'Becoming a Jackal' below: