The 27-year-old will remain at the Bombers until at least the end of the 2021 season.
“I’m thrilled to extend my contract for a further two years. I love playing at this club,” Ambrose told the club’s website.
“We have a great mix of developing talent coming through, and an experienced group of leaders so we are building towards something special.
“Ultimately, we want to continue to improve as a team and I believe this group is capable of success in the coming years.”
Ambrose has played 80 games for the Bombers since being picked up in the rookie draft in 2014.