The Billboard Top 100 track - featuring Calvin Harris - was the lead single from Rihanna's 2011 album Talk That Talk.
Rihanna also appeared in the list at number 19 with her song 'Where Have You Been'.
Flo Rida finished up in second place with his song 'Good Feeling'.
'Good Feeling' appeared on the rapper's fourth studio album Wild Ones, which was released earlier this year.
Flo Rida also had two entries in the Top 20, as his song 'Wild Ones' featuring Sia finished up in eleventh place on this year's airplay chart.
Other acts appearing twice in the Top 20 included Katy Perry with 'Wide Awake' and 'The One That Got Away', and Nicki Minaj with 'Starships' and 'Turn Me On', her collaboration with David Guetta.
The 20 most played songs on US radio in the past year are as follows:
1. Rihanna and Calvin Harris - 'We Found Love'
2. Flo Rida - 'Good Feeling'
3. The Wanted - 'Glad You Came'
4. Ellie Goulding - 'Lights'
5. Gotye and Kimbra - 'Somebody That I Used To Know'
6. Carly Rae Jepsen - 'Call Me Maybe'
7. fun. featuring Janelle Monae - 'We Are Young'
8. Maroon 5 featuring Wiz Khalifa - 'Payphone'
9. Kelly Clarkson - 'Stronger (What Doesn't Kill You)'
10. Nicki Minaj - 'Starships'
11. Flo Rida featuring Sia - 'Wild Ones'
12. Adele - 'Set Fire to the Rain'
13. Bruno Mars - 'It Will Rain'
14. One Direction - 'What Makes You Beautiful'
15. LMFAO - 'Sexy and I Know It'
16. Katy Perry - 'Wide Awake'
17. Jessie J - 'Domino'
18. David Guetta featuring Nicki Minaj - 'Turn Me On'
19. Rihanna - 'Where Have You Been'
20. Katy Perry - 'The One That Got Away'
Watch Rihanna and Calvin Harris's music video for 'We Found Love' below: