Their script, Legless, topped the scoring charts from the judges.
This is the second time Sweeney has made the final five of the competition. His writing partner said this upon finding out they had won: "This is fantastic news, we're both dead chuffed to have won the Short Com TV Sitcom script writing competition. If the BBC Head of Comedy is reading this, we're all yours."
The organisers say: "Just as the previous year, the quality of the shortlisted scripts were of a real high calibre that made it a tight contest."
Second place went to NHS doctors Rahul Neelamkavil and Rohin Francis for Off Legs. Meanwhile the writing team of Kirstie McHugh, Adam Zeitoun, Dylan Thomson and Roger Jenisch picked up third place for their script The Wonderfuls. Chloe Page came fourth with her script Amateurs and Sean Keeley was fifth with B-Negative.
The shortlisted writers will have their scripts put forward to the industry, with the top three promoted on the script platform Ink Tip. Additionally, Sweeney and Scott will receive a copy of Final Draft and BCG Pro membership.
The competition will return in 2022 with submission dates to be announced.