The 1972–73 Boston Celtics season was their 27th in the National Basketball Association (NBA).
The Celtics finished the season with the best record in the league, and currently in franchise history, at 68–14.
Third-year center Dave Cowens won the NBA Most Valuable Player Award ahead of Kareem Abdul-Jabbar and Tiny Archibald.
They also won the Atlantic Division for the second consecutive season.
In the Eastern Conference finals, the Celtics lost to the eventual NBA champion New York Knicks in seven games.