With the win, the Tigers (15-8, 8-4 Southeastern Conference) stretched their home record to 12-1 on the season.
Florida (16-7, 8-4) has now lost three straight to LSU.
LSU scored 18 of its last 23 points from the line. Antonio Hudson scored 16 points for LSU, Darrel Mitchell added 15 and Glen Davis had 11.
Anthony Roberson and Matt Walsh each had 17 for the Gators, who trailed 38-32 at the starting the second half on a 9-2 run. To take a 41-40 lead. The Tigers countered, going 10-3 over the next two minutes. The run put them up 50-45.
The Gators cut LSU's lead to 52-51 with 10:17 left on a dunk by Adrian Moss. It was the closest Florida would get.
Hudson's 3-pointer with 4:33 left gave LSU a 65-55 lead with 4:33 left. The Tigers made eight of those 10 points at the free throw line.
Walsh pulled Florida within two, 67-65, with 2:38 left. After a basket by Hudson, Roberson sank two free throws to make it 69-67 LSU.
LSU, which made its final field goal at 2:04 - a jumper by Hudson - made 8 of 10 free throws down the stretch to seal the victory. Down by two the Gators forced a long three-point attempt by Tack Minor that hit the front of the rim and bounced out but LSU grabbed the loose ball and closed the game out at the line.
Florida returns to action on Wednesday night when Vanderbilt comes to town for the second to last home game for the Gators. Game time is 8 p