He had been in hospital since the incident in Blanchardstown.
Gardaí have launched a second murder investigation following the death of the man who was shot in a restaurant in Dublin on Christmas Eve.
48-year-old Jason Hennessy was pronounced dead at the Mater Hospital today.
His alleged attacker, Tristan Sherry, was stabbed to death during the incident, and three people have been arrested in connection with his death.

Criticism Over "Extremely Slow" Psychological Evaluation Of Teenage Girl Charged With Alleged Fatal Assault Of Scarlet Faulkner
Bertie Ahern Stands Over Immigration Comments
RTÉ Includes Derek Mooney In Revised 2024 Top Earning Presenters List
Fresh Appeal For Kyran Durnin, Who Would Have Turned Ten Today
Domestic Abuse Reports Reach All Time High, With Over 1,000 Reports Made Per Week
Impact Of AI On Public Service Work The Focus At Today's Fórsa Conference
Highest Inflation Rate Since January 2024 Recorded As Consumer Prices Rise
48-Hour Planned Strike By Frontline Ambulance Staff Called Off