The 27-year-old younger brother of Watford star Troy has been a vital member of the Bucks squad over the last couple of seasons.
He joined in January 2018 and helped Rob Edwards's side seal National League North survival before playing a big part in last term's FA Trophy run and near miss with the play-offs under Gavin Cowan.
Combative midfielder Deeney made 45 appearances in all competitions for Telford last campaign, scoring four goals.
His commitment is another boost for Cowan, who has already had many of last season's squad agree fresh terms.
Skipper Shane Sutton, young goalkeeper Andy Wycherley, defender Ross White, midfielder James McQuilkin and striker Andre Brown are just some of those who are staying with the club.
The future of 26-goal top scorer Daniel Udoh remains uncertain though.