A fantastic performance by Campbell's Jack Howard helped his team to the Danske Bank Medallion Shield after a comfortable win over Wallace High in the final at Ravenhill.
Howard, who scored twice in each of the previous rounds ran in for a solo effort and also had a hand in one of the others.
This was expected to be a closely fought encounter but Campbell adjusted much better in the strong wind and rarely let their opponents into the game.
This win was a long time coming for the Belmont side as they last won the trophy 20 years ago while Wallace were looking for their first outright victory.
Campbell won the toss and played into the strong wind but during the period Wallace had most of the play and failed to convert their advantage into points.
Campbell attempted to play open rugby whereas their opponents appeared content to keep the ball tight.
The Belmont team took the lead with a well executed try. The ball was passed along the three-quarters by Nicholai Koplensky and Howard before flanker Matthew Crowther dummied and just made the line.
This set- back to Wallace, who had missed a kickable penalty, re- concentrated their determination as they took up a position close to their opponent's line for the final ten minutes of the half.
They pressurised the whole time but could not break through and Campbell eventually pushed them into touch and it was half-time.
Campbell coach Johnny Cubitt was full of praise for his team's first half efforts
He said: "It was very difficult to gain any momentum so I would have been content to turn round level so to have a five point advantage was a bonus."
After the restart Campbell controlled the possession and out-half Paddy Beverland kicked intelligently into the corners.
Wallace made a few ventures into their opponent's territory but they all came to nothing. Their centre Ben Finlay, who hails from a sporting family, looked dangerous with a couple of penetrating runs but the support wasn't there to carry on.
After this the Wallace effort was spent as their opponents were rewarded for their pressure with two late tries.
Beverland was next to touch down when he stepped inside the Wallace defence to go under the posts.
John Crowther, the brother of Matthew, added the conversion to make it 12-0. The Crowthers' father Sean was a former Ulster player who turned put for Bangor Grammar when they won the Medallion Shield and also clinched the Schools' Cup on two occasions.
With five minutes remaining the Belfast team added the best try of the final.
Three-quarters Justin Savage and Josh Haslett were involved before Howard gained possession inside his own half. He cut away and, with a couple of decoy runners, side-stepped through the defence and ran around the full back to score.
Campbell had owed their victory not only to the backs but also the forwards who took on the large Wallace pack.
Coach Cubbitt was thrilled with the result saying: "We benefitted from the strong elements but full credit to Wallace who played a tight game.
"We kept attacking and exposed them well leading to the three tries.
"We were breaking tackles with the much of the inspiration coming from Jack Howard.
"He made at least seven line breaks but was ably assisted by the remainder of the side.
"We had to perform at our best as we knew Wallace's record so far this season."