1965–66 Boston Celtics season Game log January

| Game | Date_ | Opponent | Score | Location_Attendance | Record |
|---|---|---|---|---|---|
| 42 | January 18 | Detroit Pistons | 115–116 | Philadelphia | 29–13 |
| 43 | January 19 | Baltimore Bullets | 129–89 | Boston Garden | 30–13 |
| 44 | January 21 | Cincinnati Royals | 113–96 | Boston Garden | 31–13 |
| 45 | January 22 | @ Baltimore Bullets | 107–132 | Baltimore Civic Center | 31–14 |
| 46 | January 25 | @ Cincinnati Royals | 101–113 | Cincinnati Gardens | 31–15 |
| 47 | January 27 | Detroit Pistons | 131–112 | Fort Wayne, IN | 32–15 |
| 48 | January 28 | Detroit Pistons | 105–108 | Boston Garden | 32–16 |
| 49 | January 29 | @ New York Knickerbockers | 119–107 | Madison Square Garden | 33–16 |
| 50 | January 30 | New York Knickerbockers | 118–115 | Boston Garden | 34–16 |