Pau Gasol, Andrew Bynum and Lamar Odom all had eight points a piece for Los Angeles. Ron Artest and Derek Fisher each had three points.
Paul Pierce had 16 points to lead Boston. Kevin Garnett, who suffered a minor head injury midway through the second quarter, had six points, five rebounds and four assists.
Ray Allen had nine points, Glen Davis totaled six points and Nate Robinson added five points for the Celtics.
Boston shot 51.4% from the floor while L.A. made 38.8% of its shots in the first half.