List of number-one singles of 2009 (Ireland)

This is a list of the IRMA's Irish Singles Chart Top 50 number-ones of 2009.

The X Factor winner Joe McElderry 's debut single The Climb (song) was the Christmas number one of 2009
The Black Eyed Peas stayed at number one for 12 weeks with I Gotta Feeling
Lady Gaga gained three number one in 2009 with Just Dance , Poker Face and Bad Romance .
Cheryl Cole's debut single, Fight for This Love , stayed at number one for four consecutive weeks