The British singer-songwriter was the most 'scrobbled' artist by users of the music social networking site in 2011, ahead of Lady GaGa and Foster the People.
The chart shows the most listened-to artists of the year who in some way released new music in 2011. Britney Spears and Natalia Kills completed the top five.
Foo Fighters, Radiohead, Avril Lavigne and Coldplay were among the other artists inside the top 20 for the year.
Adele secured over 800,000 different listeners on the site in 2011, while second-placed Lady GaGa was far behind with over 460,000.
Last.fm users 'scrobble' music by either using the website's radio stations or by using a plug-in with their preferred music player to note down their listening habits.
Dave Grohl of Foo Fighters recently said that Adele's 21 is an "amazing" album.
> Adele to make live performance comeback at Grammys Awards 2012?
The top 20 in full:
2. Lady GaGa
3. Foster the People
4. Britney Spears
5. Natalia Kills
6. J. Cole
7. The Strokes
8. Foo Fighters
10. Avril Lavigne
11. Christina Perri
12. Fleet Foxes
15. Bon Iver
16. James Blake
17. The Vaccines
19. Diddy - Dirty Money
20. The Naked and Famous
Watch the video for Adele's 'Rolling in the Deep' below: