Spencer Ware and Michael Ford each ran for 3.
LSU (2-0) had no hangover following its 40-27 victory over then-No. 3 Oregon last week, as the Tigers outgained the Demons, 400-95.
Jarrett Lee and Zach Mettenberger had no problems with the Northwestern State secondary, combining for 225 yards and two touchdowns.
"I liked the way our team played this game. I felt that we came out and played with intensity in all three phases," LSU head coach Les Miles said.
Brad Henderson passed for just 74 yards with an interception on 16-of-26 throws for the Demons (1-1), who rallied to beat Delta State in their season opener.
The competition was much different on Saturday, and LSU wasted little time showing it as Lee and Rueben Randle connected on a 43-yard gain on LSU's first play from scrimmage. Deangelo Peterson's nine-yard touchdown grab capped the march.
Northwestern State penetrated Tigers territory on its next two possessions, but managed only a 44-yard field goal by John Shaughnessy in the opening minute of the second quarter.
Ware scored from one and six yards out, respectively, on the ensuing LSU drives, the latter of which was set up by Michael Brockers' interception deep in Northwestern State territory.
Lee completed three passes for a total of 49 yards in the final minute of the half, allowing enough time for Ford to go in for a three-yard score and a 28-3 cushion at the break.
Ford started the second half where he left off the first, as he ran up the gut for a seven-yard TD 2 1/2 minutes in.
Alfred Blue extended the lead with a four-yard run to paydirt later in the third, and Mettenberger hooked up with Kadron Boone for a 19-yard score in the final frame.
"[LSU] is definitely the number one team in the country. They are a great football team," said Northwestern State head coach Bradley Dale Peveto.
LSU has won 35 straight non-conference regular season games, a streak that dates back to the 2002 season...LSU is 11-0 all-time against Northwestern State, though the programs had not met since 1942....The Tigers have also won 12 in a row at home...Northwestern State head coach Bradley Dale Peveto was an LSU assistant from 2005-08.