Rins replaces Morbidelli at Yamaha for 2024 MotoGP season
The 27-year-old will move from Honda who he joined only this year and won the Americas MotoGP, the team's first victory since 2021.
However, he broke a leg in the sprint race at the Italian Grand Prix in June and is still out of action -- he will miss this weekend's British MotoGP.
"We expect Alex to be a great asset," said Yamaha's managing director Lin Jarvis in a statement on the team's website.
"He has vast experience as a MotoGP rider and is known to be a natural talent and a multi-time MotoGP class race winner.
"His win earlier this year underlines his speed, hunger, and determination to succeed."
Rins, the championship runner-up in 2020 who has six MotoGP victories to his credit and 12 other podium finishes since he made his debut in 2017, replaces Franco Morbidelli.
The 28-year-old Italian has recorded three victories and three other podium finishes since he joined Honda in 2019.
"The Yamaha and Morbidelli partnership led to some great results, including an outstanding vice-champion title in 2020," said Jarvis.
"It's a shame that the last two years didn't play out the way we both wanted and hoped for.
"We discussed the possibilities to continue our partnership, but ultimately we decided that 2024 would be a moment to make a change, both for Yamaha and for Franky."