Jose Morais will take over as head coach at Jeonbuk Hyundai Motors after long-serving incumbent Choi Kang-hee departs at the end of the season, the K-League champions said.
Morais, who has worked under Manchester United manager Jose Mourinho during spells at Benfica, Inter Milan, Real Madrid and Chelsea, will become the club's first foreign coach.
"Given his wealth of experience in European football, we felt Morais was the perfect coach for our club's philosophy," Jeonbuk were quoted as saying by the Yonhap news agency on Thursday.
Choi guided Jeonbuk to six league titles and two AFC Champions League triumphs over two spells, the first beginning in 2005, and is set to leave for Chinese club Tianjin Quanjian.
Morais linked up with Mourinho during a brief stint at Benfica before joining his compatriot at Inter Milan in the 2009-10 season, where they guided the club to the Serie A, Champions League and Italian Cup titles.
The pair then moved to Spain, where they helped Real Madrid claim a league and cup double, before joining forces at Chelsea, where they won a Premier League title in 2014-15.
The 53-year-old Morais has also coached in Tunisia, Saudi Arabia, Turkey, Greece, England and Ukraine.
His arrival follows the appointment of compatriot Paulo Bento as South Korea coach in August.
Former Portugal boss Bento has enjoyed a bright start, with the team going undefeated in six games to enhance their status as one of the favourites for next year's Asian Cup.
Jeonbuk won their second-straight league title in October with six matches remaining. They finish their campaign against Gyeongnam FC on Sunday.