The West Tipp side defeated Bandon 12-10 in the final, which was played in Charleville.
It's their first victory in the competition in quarter of a century.
Meanwhile, Clanwilliam are through to the quarter-finals of the Bank of Ireland Munster Junior Cup.
They booked their place in the last eight by defeated Cobh Pirates 21-9 in a re-arranged tie in Cork.
