Belvo' playing with the advantage of the wind in the opening half made the better start and a great break by full back Daniel Riordan sent David Mongan in for a try in the corner which Andy Dunne converted after eight minutes.
Con' dominated the opening half and Scott Deasy, Denis Fogarty and Brendan Cuttriss were all stopped short of the line as Con' went in search of an opening try. Ian Nagle and Stephen Archer were doing an amount of work in the loose but three penalties from Gerry Hurley on eleven, twenty and thirty six minutes gave the holders a 9-7 half time lead.
John Kennedy restored Belvo's lead early in the second half with a well worked try, but Sean Scanlon put Con' two points ahead with a try after good work by Deasy and Simon Zebo minutes later.
Out half substitute Conal Keane kicked a penalty for Belvo' after a drop goal effort came back off the post to lead 15-14.
With eleven minutes remaining Belvo' extended their advantage when Kennedy touched down in the corner for his side's third try.
Con' kept in the hunt with Hurley kicking his fourth penalty with eight minutes remaining but the reliable scrum half was off target with an effort three minutes from time.
Belvo' than played out time for their first All Ireland League title.
Scorers Cork Constitution: Sean Scanlon try, Gerry Hurley 4 pens.
Old Belvedere: John Kennedy 2 tries, David Mongan try, Conal Keane pen, Andy Dunne con.
Cork Constitution: Sean Scanlon; Richie Lane, Cyprian Jouve, Ivan Dineen, Simon Zebo; Scott Deasy, Gerry Hurley; Martin Gately, Denis Fogarty, Stephen Archer; Brian Hayes, Ian Nagle ; Brendan Cuttriss, Billy Holland, Frank Cogan (capt). Replacements used: Robert Quinn for Fogarty (30 mins-half-time, blood sub), Duncan Williams for Jouve, Robert Quinn for Fogarty (both 43), Peter O'Mahony for Cuttriss (45).
Old Belvedere: Daniel Riordan; Eddie Devitt, John Kennedy, Ben Woods, David Mongan; Andy Dunne (capt), Simon Keogh; Vinny Soden, David Gilchrist, Stewart Maguire; Richie Leyden, Ben Marshall; Jonathan Slattery, Jason Risdon, Leo Auva'a. Replacements used: Chris Keane for Woods (25-34 mins, blood sub), Ben Byrne-Diaper for Slattery (33-40, temp), Conal Keane for Dunne, Chris Keane for Keogh, Kevin Buckley for Gilchrist (all 59), Dean Moore for Marshall (63).
Referee: Dudley Phillips (IRFU)