Terms of the deal were not disclosed by the team but Sportsnet's Elliotte Friedman reports Murray will be paid $2 million next season.
The 27-year-old had 14 assists in 48 games with the New Jersey Devils last season. Before that, the second-overall pick in the 2012 draft had spent his first seven seasons with the Columbus Blue Jackets.
"Ryan is an effective two-way defenceman who can provide minutes and added puck movement to our back line," Avalanche general manager Joe Sakic said in a statement. "We like the experience he brings to our locker room, and we're excited to see him fit in with our group."