Skylar Mays added 15, Aaron Epps 16, Daryl Edwards 14 and Brandon Sampson had 13.
LSU (13-9, 4-6) won for just the second time in seven games since a 75-54 victory at Arkansas on Jan. 10. The Tigers, who at home in SEC play for just the second time, visit No. 23 Florida on Wednesday.
Daryl Macon scored 22 to lead Arkansas (15-8, 4-6), which had won its last 30 games in which it had scored at least 80 points. The Razorbacks host South Carolina on Tuesday.
Jaylen Barford added 15 points, Anton Beard and Trey Thompson scored 11 each and Daniel Gafford had 10.
The Tigers' proficiency from long range helped make the difference as they made 15-of-30 3-pointers and the Razorbacks made 3-of-8.
LSU's first four baskets of the second half were 3-pointers as it extended an eight-point halftime lead to 55-43.
The Razorbacks trimmed the lead several times, but could not make a sustained run.
Macon made a 3-pointer and converted a three-point play as Arkansas closed within 61-57.
But Waters and Mays each made a 3-pointer as the Tigers took a 78-67 lead.
The Razorbacks scored five straight but Waters and Mays made two free throws each to put the margin at 10 with 3:28 left.
Arkansas got no closer than eight points until the final 22 seconds, when it didn't have enough time to catch up.
LSU made 6-of-13 3-pointers, including 3-of-4 by Edwards, as it raced to a 28-16 lead.
Arkansas made just nine of its first 27 shots and the Tigers used a 10-0 run to grab the 12-point lead.
Thompson's jumper ended the drought and started a 9-2 run that got the Razorbacks within 30-25.
The Tigers rebuilt the lead to 10 points on three occasions before Dustin Thomas' jumper with 33 seconds left cut the margin to 43-35 at halftime.
--Field Level Media
Arkansas | Louisiana State | |
Daryl Macon 22 | Scoring | Tremont Waters 27 |
Daryl Macon 5 | Assists | Tremont Waters 11 |
Jaylen Barford 4 | Rebounds | Wayde Sims 6 |
Daryl Macon 6 | Free Throws Made | Tremont Waters 9 |
Jaylen Barford 2 | Steals | Skylar Mays 1 |
Daniel Gafford 1 | Blocks | Aaron Epps 2 |
Team | Points | FG% | 3PM-3PA | FTM-FTA | Assists | Rebounds | Blocks | Steals | Turnovers |
Arkansas | 86 | 55.0 | 3-8 | 17-24 | 12 | 28 | 2 | 8 | 11 |
Louisiana State | 94 | 52.7 | 15-30 | 21-23 | 17 | 24 | 7 | 2 | 12 |