The Scottish back has been training with the squad over the last few weeks and impressed for the Warriors in the recent 'A' fixture with Edinburgh.
The 26-year-old has played for Stirling County, Aberdeen Grammar and for clubs in Canada.
Fraser told glasgowwarriors.org: "I'm very grateful for this opportunity to play professional rugby.
"I know I have to keep working hard and hopefully I'll get as much game time as possible.
"I want to learn from all the players and coaches at the club and make the most of this move."
Head coach Gregor Townsend added: "We've been watching Fraser for some time and he's been in great form for Stirling County this season.
"Fraser trained with us a few times last season and played well in our 'A' fixture with Edinburgh Rugby.
"He has worked extremely hard to earn this full professional deal and he'll add to the competition in the back-line, increasing our depth primarily at 10 and 12."