The 2008 League of Ireland First Division season was the 24th season of the League of Ireland First Division.
The regular season began on 7 March and concluded on 15 November.
This was because the 2009 Premier Division would be reduced to 10 clubs.
[2] Kildare County and Mervue United, the highest ranked non-reserve team from the 2008 A Championship, played off to see who would play in the 2009 First Division.
Mervue United won 5–2 on aggregate and were promoted to the First Division.