Lecavalier was hurt in Thursday's game at Washington. His shoulder was dislocated when he fell awkwardly after a hit by Washington's Matt Cooke.
Tests on Friday showed Lecavalier damaged the labrum of the right shoulder. A date for surgery and the establishment of a rehab schedule will be determined in seven to 10 days, after inflammation subsides.
Recovery time is expected to be 12 to 15 weeks, which means Lecavalier could be ready for the start of training camp this fall.
"While I'm disappointed to be facing surgery at this time, I'm looking forward to working hard during the summer to be ready for training camp in September," Lecavalier said in a statement.