Broja suffered the injury in a mid-season friendly game against Aston Villa on Sunday which Chelsea lost 1-0.
The 21-year-old Albania international, who signed a new six-year deal at Stamford Bridge this summer following an impressive loan spell at Southampton last season, has made 18 appearances across all competitions for Chelsea this season, scoring one goal.
The injury leaves Chelsea with Pierre-Emerick Aubameyang as the only remaining out-and-out striker and they could dip into the January transfer market for a solution.
Chelsea said in a statement: "Having sustained a knee injury during the first half of Sunday's friendly against Aston Villa, Armando underwent further assessment following the club's return to England.
"Scan results from those assessments have unfortunately confirmed an anterior cruciate ligament rupture and that surgery will be required.
"Following the operation, Armando will work closely with the club's medical department during his rehabilitation and is expected to miss the remainder of the 2022/23 campaign."
Chelsea will return to Premier League action after the conclusion of the Qatar 2022 FIFA World Cup against Bournemouth on December 27 looking to improve upon their current eighth position, which sees them 16 points behind leaders Arsenal.
