The lock has committed to the club until at least 2021 and becomes the ninth player to put pen to paper in the past two weeks.
A product of the Fosroc Scottish Rugby Academy, Cummings was still an Academy player when he made his Warriors debut against Scarlets in 2015.
He scored a try the following week against Connacht and signed his first professional deal in 2016, playing simultaneously for Glasgow Hawks that season in the Tennent's Premiership.
A Glasgow Warriors supporter growing up, Cummings has since gone on to play 46 times for the club, scoring 6 tries.
He first played rugby for Kelvinside Academy where he was the first XV captain. He represented Scotland through the age-grades, captaining Scotland U20s at the 2015 World Championships in Manchester.
Gregor Townsend invited Cummings to train with the national squad during the 2017 Autumn Internationals.
Speaking to glasgowwarriors.org, Cummings said: "I'm delighted to be staying. I've loved my time here so far and I'm looking forward to another two seasons at least.
"I used to come to Scotstoun as a fan, so it's extra special to now run out as a player and I'm really excited by the potential of this group."
Head Coach Dave Rennie said: "Scott's a good man and has been a key part of our forward pack during my time here.
"He's an excellent line out forward and a really impressive athlete and it's great news that he's staying for another two years at least."