The new deal will see him remain with the famous club until at least the end of 2025.
The half is touted as one of the best young stars in the game, and has impressed during his six opportunities to play first-grade across the back end of 2020, and through the 2021 season.
Three of those games also came at hooker at the back end of 2021 as the Dragons grappled with something of an injury crisis.
He impressed out of position though, and has made more than a justifiable case that he belongs in first-grade.
It was reported however that he had previously turned down a contract extension, although it's not clear if the Dragons increased their offer to keep the star.
Sullivan, who led the Dragons to the SG Ball title in 2019 alongside Tyrrel Sloan and Talatau Amone, is one part of the trio who will likely form the future of the club, although Sullivan and Amone could well be forced to fight for a single spot in 2022 with Ben Hunt still at the club.
Regardless of that likely scenario, Sullivan said he couldn't be any happier to re-sign.
"To be able to stay home and continue my career in front of my friends and family, I couldn't be any happier. The club means a lot to me," Sullivan said.
"I'm excited to bring some joy to the Red V. I feel like we're building something special here and I can't wait to see what the future brings."
Dragons' general manager of football Ben Haran said Sulliva was a key factor in the club's list management going forward.
"Jayden's continued commitment to the Dragons beyond the upcoming 2022 season is something everyone connected to the club should be extremely pleased and proud of," Haran said.
"Jayden is a proven example of our pathways providing opportunities for players to progress through to the NRL level.
"We look forward to seeing him grow as a player over the coming years. He is a great young person to have around the club and he is another important part in the future of the Dragons."