Bardghji, who was born in Kuwait but plays for Sweden, suffered a serious knee problem during training in 2024 that sidelined him for nearly a year.
"The player will undergo surgery in the coming days," Barca posted on social media platform X after the latest setback.
Bardghji joined Barca from Copenhagen last year on a contract that runs until June 2029.
He has made 28 appearances for Barca in all competitions, scoring two goals and providing four assists.
Bardghji has won three caps since making his senior debut last year but missed selection for Sweden's 2026 World Cup squad.
Hansi Flick's Barca side, who are chasing a third straight LaLiga title, open their league campaign at Elche on August 23rd.