Boutte will sit out LSU's home opener against Jacksonville State on Saturday night.
"Josh made a mistake and will serve a one-game suspension because of it," LSU coach Les Miles said in a statement. "Even though this was done by mistake, a play like this does not belong in the game of football and therefore action must be taken.
"This play does not define Josh as a person and is not indicative of the type of player he is. We sincerely apologize for his mistake."
Boutte called Dixon on Monday morning to personally apologize for the personal foul, Miles said.
Boutte, a starting guard for the Tigers, was ejected after leveling Dixon with 57 seconds left in No. 5 LSU's 16-14 loss to Wisconsin at Lambeau Field. Dixon intercepted Brandon Harris' pass near the LSU sideline to seal the upset win, and following the play, he started celebrating with the ball and his hand raised when Boutte hit him.
SEC commissioner Greg Sankey issued a statement on the suspension.
"I have accepted the one-game suspension imposed by Les Miles and, because LSU has taken appropriate action, have determined that no additional penalty shall be imposed by the Conference office," he said.