The 28-year-old activated a relegation release clause in his Newcastle contract after the Falcons dropped out of the Premiership this term.
And now the eight-cap Scotland international will bolster the Cherry and Whites’ resources next season.
Gloucester director of rugby David Humphreys told the club’s website: “We’re delighted that Chris has agreed to join Gloucester Rugby and to add another international calibre player to the squad, one who also possesses significant Premiership experience.
“As is the case will all Premiership clubs, there are times when the squad is tested to the max due to injuries and international commitments, for example.
“Chris is a proven talent, a quality player and will add to our options in the backline.”
Carlisle-born Harris made 77 Premiership appearances for Newcastle, having come through the club’s academy and studied at Northumbria University.
Harris admitted his move had been driven by the desire to remain at the top level of the domestic game.
“It’s all happened very quickly to be honest,” said Harris.
“I’ve loved every minute of my time with the Falcons and will be forever grateful to them.
“However I’m at the stage of my career where I need to be performing at the highest level of the club game.
“Watching from outside I’ve been so impressed with what Gloucester Rugby have done over the past couple of seasons and can’t wait to link up with my team-mates and start to contribute.
“They seem to have a great team culture and play some entertaining rugby.
“I’ve always enjoyed playing at Kingsholm so it promises to be an exciting new chapter.”
Sign up to our mailing list here and we’ll keep you up to the minute with weekly updates from the world of rugby.