The Scottish international will remain at the Dragons until at least the end of the 2020 season.

"The St George Illawarra Dragons have been a good club to me. I've been here through all my junior years and come through the ranks to now first grade," Aitken said.

"It was an easy decision to re-sign for a further three years, I really enjoy it here and I really like the direction the Club is heading and I want to be a part of it".

A graduate of the Dragons' junior representative and Holden Cup teams, Aitken made his debut in Round 3, 2015 and has played 45 NRL games to date.

He made his Country Origin debut in 2016 and played for Scotland at the recent Four Nations tournament in the United Kingdom.

Dragons director of rugby league Ian Millward said Aitken's retention was crucial for the future success of the club.

"It's always exciting when one of your own re-signs, especially a player and person like Euan," he said.

"He's only a young man who in two years has made his representative debut. He's a player that everyone loves playing with and he'll only improve.

"He's also one of the fittest players in our club and a player who we see will lead the way in future years. We're very excited for Euan."