Old Belvedere scored the only try but Gavin Dunne's hat-trick of penalty goals was enough to guide UCC into the AIB Cup quarter-finals at the Mardyke.
Belvedere winger Dave Mongan dotted down in the closing stages of this lively tie, adding to a penalty from centre Eamonn Fitzgerald.
But, in tricky conditions, the assured Dunne won the day for the Cork students, who led 6-3 at half-time.
After going 8-6 down, UCC's hard-working pack eked out a final chance for Dunne which he gleefully took.
Scorers:
UCC: Pens: Gavin Dunne 3
Old Belvedere: Try: Dave Mongan; Pen: Eamonn Fitzgerald
