Gloucester sign Springbok World Cup-winner Kleyn
He will join the Cherry and Whites after 10 years with Irish province Munster.
Kleyn has been capped 10 times by the Springboks since his debut in 2023 and came off the bench for that year's World Cup final win against New Zealand.
He has also represented Ireland, playing five matches, including two at the 2019 World Cup, having qualified on residency grounds after signing for Munster three years earlier.
"Jean is a player I've admired for a long time," said Gloucester director of rugby George Skivington.
"He brings real edge, experience, and a winning mentality, which will be invaluable for our group."
The 32-year-old Kleyn, who won the 2022/23 United Rugby Championship title with Munster, added: "I'm thrilled to be joining Gloucester Rugby next season.
"It's a club with incredible history and a passionate fan-base, and the vision shared with me really matched what I was looking for in the next chapter of my career."
Gloucester are currently ninth in the 10-team Prem, but Kleyn is the fourth player the club have signed for next season, following Wales duo Jac Morgan and Dewi Lake and scrum-half Dan Robson.