Garryowen jumped into the lead with a penalty from Jamie Gavin inside the opening minute.
Darragh Lyons missed a penalty for Con' from the restart and despite a torrential shower of rain, Con' playing into the elements dominated with an excellent display by skipper Gerry Hurley. Two Lyons penalties had Con' in front by the end of the first quarter, a lead they held until half time.
Both sides missed penalties in the opening ten minutes of the second half as Garryowen began to take control in the forward exchanges. Despite their possession Garryowen were unable to convert this into scores.
Niall Kenneally made a few breaks that threatened to open the Garryowen defence as the game entered the final five minutes.
Con's James Ryan was yellow carded with four minutes remaining and Chris Quinn had a penalty effort for Con' two minutes from time but his effort went wide.
One final effort saw Gavin level in the third minute of injury time to send the game into extra time.
Two minutes into extra time Gavin tried a drop goal effort which went wide but a minute from the end of the first period of extra time Gavin saw a penalty effort come back off the posts but Con' were again penalised and Gavin's effort was again off target.
With time running out Con' made one effort to save the game and Chris Quinn landed a thirty five meter penalty to give Con' the trophy for the 25th time.
Garryowen: Lorcan Burke; Steve McMahon, Conan Doyle, Alan Gahan, James McInerney; Jamie Gavin, Neil Cronin; Rory Brosnan (Capt.), James Rael, Peter O'Shea; Aaron McCloskey, Darren Mulcair; Shane Buckley, Anthony Kavanagh, Mark Rowley
Replacements: Ed Rossiter, JP Cooney, Alex Vaclu, Mark Hanrahan, Harry McNulty, Andrew O'Byrne, Geoff Ryan.
Cork Constitution: Chris Quinn: Cathal Quinn, Luke Duffy, Niall Kenneally, Conor Desmond; Darragh Lyons, Gerry Hurley (Capt.); Gavin Duffy, Andrew O'Driscoll, Ger Sweeney; Joe McSwiney, Cathal O'Flaherty; Graham Lawlor, James Ryan, Luke Cahill.
Replacements: Max Abbott, Brian Cagney, Sonny Dwyer, Rory Burke, Yasin Browne, Ryan Foley, Rob Jermyn.
Referee: K Barry (M.A.R.).