Scotland U20 captain Jonny Gray has signed a three-year professional contract with the club, while hookers Fraser Brown and Kevin Bryce have agreed one-year deals.
19-year-old Jonny Gray has been part the Scottish Rugby Elite Development Programme this season, after joining the club last summer from Hamilton.
Prior to joining the Warriors, the second row trained and played rugby in New Zealand, having been named as one of the recipients of the 2012 John Macphail Scholarship.
Jonny was called up to the Scotland under-20 set-up at the age of just 17 and was made captain when he returned to the national age-grade squad for the 2013 RBS 6 Nations.
This season he has made two appearances off the bench for Glasgow, in the wins over Edinburgh and Newport Gwent Dragons.
Jonny said: “I’m honoured to have agreed a professional contract with the Warriors. I’ve really enjoyed working with the squad, who have all made me feel very welcome since I joined the club and I’m grateful for the experience in the PRO12 this season.
"The set up at Scotstoun is excellent and it’s the perfect platform for me to develop as a player. Competition is tough with the talent we have here, but the players have been great and continually offer me advice, which has helped a lot.
“I’m really looking forward to continuing my career in Glasgow over the next three years.”
Meanwhile, Glasgow Warriors have also signed two highly rated club rugby hookers for next season.
Fraser Brown and Kevin Bryce arrived at Scotstoun earlier in the season from Heriot’s to provide cover and both players have now signed one-year deals with the club.
24-year-old Kevin, a former Stirling County player, has represented Scotland at U18, U19, sevens and club international level. In 2007 he was the recipient of the John Macphail Scholarship, which saw him play club rugby in New Zealand.
23-year-old Fraser, who has made three appearances for Glasgow in the RaboDirect PRO12 this season, previously played for Edinburgh, Biggar, Melrose and Watsonians and has represented Scotland at age-grade, sevens and club international level.
Fraser said: “I’m very happy to have extended my stay in Glasgow. I’ve enjoyed learning from the quality players that I’m working with every day at Scotstoun and being able to stay here next season will help me continue my development as a player.”
Kevin added: “There is a lot of competition for the number two jersey but that motivates me even more to try and break into the team. I’m delighted to get the opportunity to stay at Scotstoun and I’m looking forward to getting a full pre-season under my belt.”
Glasgow Warriors head coach Gregor Townsend said: “It is fantastic news for the club that Jonny will be staying here for at least the next three years and that Kevin and Fraser have signed up for next season.
“Jonny has so much ability and does everything asked of him on and off the pitch.
“He’s played a couple of times in the league this season and shown us what he is capable of. He has also played regularly for Currie in the Scottish Premiership and captained the Scotland U20 team, so he’s definitely ready to take the next step up.
“Kevin and Fraser have been involved with us this season and their work ethic has impressed me. We’ve seen at first hand what they're capable of in a professional environment and they will be excellent additions.”
Glasgow Warriors forwards coach Shade Munro added: “Jonny continues to improve and always puts a huge amount of effort into training and games. He works extremely hard and is focused on developing his game.
“There is a lot of competition for places in the second row just now but Jonny deserves this opportunity and he undoubtedly has a big future ahead of him.
"Fraser and Kevin are two of the most highly rated hookers in the club game in Scotland and we’re delighted to have secured them for next season.
“Both players have looked sharp and shown a desire to do well in training since they arrived here and they will add competition to our squad.”