Chen underwent the surgery last week in Vail, CO, but the team did not announce the procedure until Thursday night. The southpaw is expected to be ready by the start of spring training.
Orioles executive vice president of baseball operations Dan Duquette released a statement regarding the surgery:
"Wei-Yin had a procedure done on his right knee that should prevent him from future discomfort in the knee. The recovery period is three to four months, so we do not expect him to miss any time during Spring Training."
The starter missed nearly two months this season with an oblique strain. Chen ended up making 23 starts for the Orioles, going 7-7 with a 4.07 ERA.
Chen signed a three-year, $11.388 million contract with Baltimore before the 2012 season. He will be entering the final year of his contract, but the Orioles hold a club option for 2015.