The new deal will keep the 19-year-old with the Dons until the summer of 2014. Jack broke into Aberdeen’s first team last season.
“I’m really pleased to have signed the new deal. This is a massive club,” Jack told the club’s official website.
“I have come right through from the youngest age group in the youth academy to the first team. I know I have still got a lot to learn and I feel this is the right club for me to keep learning.
“I am looking forward to continuing my development as a player under the guidance of Craig Brown and Archie Knox.
“I am enjoying playing regularly and I get on great with all the lads. The club is going forward now under Craig and Archie and I am looking forward to see what we can achieve.”
