The 2005 Northern Ireland Trophy was the first edition of the Northern Ireland Trophy snooker tournament, held from 17 to 21 August 2005, at the Waterfront Hall, Belfast, Northern Ireland. Matthew Stevens defeated Stephen Hendry by nine frames to seven (9–7) in the final. Alan McManus made the highest break with 140. This was the only year the tournament was held as a non-ranking event; it would become a ranking tournament for the next three seasons.

Northern Ireland Trophy

Tournament information
Dates	17–21 August 2005 (2005-08-17 – 2005-08-21)
Venue	Waterfront Hall
City	Belfast
Country	Northern Ireland
Organisation	World Professional Billiards and Snooker Association
Format	Non-ranking event
Total prize fund	£104,000
Winner's share	£23,000
Highest break	Alan McManus (140)
Final
Champion	Matthew Stevens
Runner-up	Stephen Hendry
Score	9–7
← First 2006 →

The top 16 ranked players were invited, Paul Hunter and Stephen Lee did not participate. They were replaced by Ali Carter and 2005 World Champion Shaun Murphy. Northern Ireland players Mark Allen and Joe Swail were invited as wildcards along with Ding Junhui and Neil Robertson.