كتب : وكالات
A statement on the club's website said that scans revealed on Friday that he will be sidelined for six weeks.
The 28-year old player has been struggling with injuries over the past 12 months as he featured in only 13 of Barcelona 30 League games.
The former World Player of the Year has been out of action since March ninth.
There has been confusion over his injury as the medical staff said he has no injury but admitted he still feels pain.
The injury adds pressure on the unsettled Brazilian magician who has been linked with a move away from Camp Nou.
Ronaldinho's injury comes as a big blow for the Blaugrana who already miss midfielder Deco because of a calf injury.
The Catalan giants will face Schalke in the Champions League quarter final second leg on April ninth.