Murchie has made more than 50 appearances since joining Warriors from London Welsh in 2009.
The 26-year-old said: "My game has come a long way since I came north to Glasgow and I'm delighted to have signed on for another three years.
"I want to keep developing my game and this is the perfect place for me to do that. There is a huge amount of competition in the back line at Scotstoun but that can only improve us as a group."
Murchie is looking to celebrate by helping Glasgow follow up last week's 23-14 RaboDirect Pro12 win over Edinburgh when they travel to Murrayfield on Saturday.
He said: "The conditions last week weren't ideal but we scored three really good tries and that's testament to the way we want to play the game."