The Rose Royce cover, which also features One Direction and JLS, has pushed Rihanna's 'We Found Love' down to number two.
Sara Bereilles and Ingrid Michaelson advance to number three with 'Winter Song', Florence + the Machine tumble to two with 'Shake It Out' and Flo Rida sits at five with 'Good Feeling'.
Christina Perri's Twilight track 'A Thousand Years' moves into the top ten to seven, while Olly Murs trails at eight with 'Dance With Me Tonight'.
Katy Perry moves up a few to 14 with 'The One That Got Away', One Direction's 'Gotta Be You' takes a tumble down to 22 and The Pogues' festive favourite 'Fairytale of New York' resides at 23.
Jason Derulo's 'Fight For You' debuts at 31, while Mariah Carey's holiday classic 'All I Want For Christmas Is You' re-enters at number 37.
This week's Irish Top 10 is as follows:
1. (-) X Factor Finalists 2011 feat. JLS and One Direction: 'Wishing On A Star'
2. (1) Rihanna feat. Calvin Harris: 'We Found Love'
3. (4) Sara Bereilles & Ingrid Michaelson: 'Winter Song'
4. (2) Florence + the Machine: 'Shake It Out'
5. (5) Flo Rida: 'Good Feeling'
6. (6) Ed Sheeran: 'Lego House'
7. (11) Christina Perri: 'A Thousand Years'
8. (15) Olly Murs: 'Dance With Me Tonight'
9. (9) LMFAO: 'Sexy And I Know It'
10. (10) Maroon 5 feat. Christina Aguilera: 'Moves Like Jagger'
Watch the music video for The X Factor Finalists 2011 feat. JLS and One Direction 'Wishing On A Star' below: