This is a list of the IRMA's Irish Singles Chart Top 50 number-ones of 2009.
Contents
| Issue date | Song | Artist |
|---|---|---|
| 1 January [1] | "Hallelujah" | Alexandra Burke |
| 8 January [2] | ||
| 15 January [3] | "Just Dance" | Lady Gaga featuring Colby O'Donis |
| 22 January [4] | ||
| 29 January [5] | ||
| 5 February [6] | ||
| 12 February [7] | ||
| 19 February [8] | "Get On Your Boots" | U2 |
| 26 February [9] | "Poker Face" | Lady Gaga |
| 5 March [10] | ||
| 12 March [11] | "Do You Believe" | Julie-Anne Dineen |
| 19 March [12] | "Right Round" | Flo Rida featuring Ke$ha |
| 26 March [13] | ||
| 2 April [14] | ||
| 9 April [15] | "Jai Ho! (You Are My Destiny)" | A.R. Rahman & The Pussycat Dolls featuring Nicole Scherzinger |
| 16 April [16] | ||
| 23 April [17] | "We Made You" | Eminem |
| 30 April [18] | "Poker Face" | Lady Gaga |
| 7 May [19] | "Number 1" | Tinchy Stryder featuring N-Dubz |
| 14 May [20] | ||
| 21 May [21] | ||
| 28 May [22] | ||
| 4 June [23] | ||
| 11 June [24] | "Untouched" | The Veronicas |
| 18 June [25] | "When Love Takes Over" | David Guetta featuring Kelly Rowland |
| 25 June [26] | "My Baby's Waiting" | Industry |
| 2 July [27] | "When Love Takes Over" | David Guetta featuring Kelly Rowland |
| 9 July [28] | ||
| 16 July [29] | "I Gotta Feeling" | The Black Eyed Peas |
| 23 July [30] | ||
| 30 July [31] | ||
| 6 August [32] | ||
| 13 August [33] | ||
| 20 August [34] | ||
| 27 August [35] | "Burn" | Industry |
| 3 September [36] | "I Gotta Feeling" | The Black Eyed Peas |
| 10 September [37] | ||
| 17 September [38] | ||
| 24 September [39] | ||
| 1 October [40] | ||
| 8 October [41] | ||
| 15 October [42] | "Bad Boys" | Alexandra Burke featuring Flo Rida |
| 22 October [43] | "Fight for This Love" | Cheryl Cole |
| 29 October [44] | ||
| 5 November [45] | ||
| 12 November [46] | ||
| 19 November [47] | "You Are Not Alone" | The X Factor Finalists 2009 |
| 26 November [48] | ||
| 3 December [49] | ||
| 10 December [50] | "Bad Romance" | Lady Gaga |
| 17 December [51] | "The Climb" | Joe McElderry |
| 24 December [52] | ||
| 31 December [53] |