In February 2019, Steyn joined Warriors on a one-year deal ahead of the 2019/20 season.
Steyn was available to play for his new club when he was not playing for Scotland 7s and made his debut in a 38-34 win over Cardiff Blues at the Arms Park five days after signing.
Steyn went on to play a key role in the run to last season's Guinness PRO14 Final, finishing off a memorable length of the field move in the 50-20 victory over Ulster in the semi-final at Scotstoun.
His form saw him called into Gregor Townsend's pre-Rugby World Cup training squad over the summer, his first call-up to the senior national squad in 15-a-side rugby.
He has made seven appearances to date in the 2019/20 campaign, most recently coming off the bench in Saturday's home defeat at the hands of Leinster.
"It was a really easy decision to stay at Scotstoun," Steyn told glasgowwarriors.org.
"It's by far the best environment I've been involved in during my career so far, so I'm really happy to be staying on.
"There's so much scope to get better, and I'm just focusing on enjoying my rugby and helping the Warriors challenge at the top of the standings."
Glasgow Warriors Head Coach Dave Rennie was delighted to retain the services of the South African-born back, saying: "It's brilliant to have Kyle staying with us.
"He's a good man with an excellent work ethic. Kyle made an instant impression when he arrived - starting the final nine games of last season at either centre or wing.
"He is keen to learn and I think he'll just continue to grow and get better."
A former student at the University of Stellenbosch, South African-born Steyn played 15s rugby in the Currie Cup for the Griquas and was named as the side's captain for their 2018 campaign.