The 2009–10 Boston Celtics season was the 64th season of the franchise in the National Basketball Association (NBA). The Celtics finished with a record of 50–32, a 12 win drop off from the previous season. They finished 1st in the Atlantic Division and 4th in the Eastern Conference. The Celtics would not reach the Finals again until 2022 where they faced Golden State Warriors in a rematch of the 1964 NBA Finals and lost in six games.