Los Angeles announced the move Monday. General manager Mitch Kupchak confirmed the Lakers would exercise the option.
Bynum is coming off his best NBA season after averaging career highs with 18.7 points and 11.8 rebounds while making his first All-Star team, starting for the West. He was the NBA's third-leading rebounder and 20th-leading scorer while also ranking sixth in the league with 1.93 blocked shots per game.
Bynum also avoided the injuries that have dogged him throughout a seven-year career since the Lakers made the New Jersey high schooler the youngest player ever drafted in 2005. Bynum played in 60 of the Lakers' 66 regular-season games, missing four due to suspension.