Jordan Farmer came off the bench and scored 15 of his 17 points in the final quarter as Los Angeles (3-2) kept Charlotte (0-7) winless.
The extent of Bryant's injury is not known. The Lakers said that last season's NBA Most Valuable Player will be re-examined on Wednesday.
Bryant did not speak with reporters after the victory.
"I didn't even ask him about the injury," coach Phil Jackson said. "The trainer said he hyperextended his knee somewhat. We'll see what it's like (Wednesday), then go from there."
Bryant was injured with 3:08 left in the second quarter under the Lakers' basket when he jumped for a rebound. Bryant motioned to the bench to come out and Jackson called a 20-second timeout as Bryant limped off the floor.
Bryant scored four points in 14 minutes and came out in street clothes for the third quarter.
Andrew Bynum scored 16 points, Trevor Ariza added 14 and Pau Gasol and Derek Fisher scored 12 points apiece for the Lakers in limited playing time.
Jason Richardson and Gerald Wallace each had 16 points for the Bobcats, who close out their preseason schedule on Thursday against the Lakers.