The decision was made after Aoki met with specialist Michael Collins in Pittsburgh for a second time in an attempt to get cleared to play.
Aoki suffered a concussion Aug. 9 when he was hit in the head by a pitch against the Cubs. He returned to the lineup three games later but played only five innings before running into the wall to make a catch. He was put on the seven-day concussion DL after complaining of nausea and a difficult time focusing. While he didn't have headaches, manager Bruce Bochy said there were other symptoms that led the team to put him on the DL.
He also spent time on the disabled list with a small fracture in his right fibula, missing 28 games.
The 33-year-old finished with a .287 batting average, five home runs and 26 RBIs in 93 games.
The Associated Press contributed to this report.