Webster, a native of Vacherie, La., earned first team All-America honors in 2003 from the American Football Coaches Association, while being a second team All-America by SI.com and collegefootballnews.com.
"After talking with Coach Saban and my family, I have decided to return to LSU for my senior season," Webster said. "My first four years at LSU have been great, winning two SEC titles and the national championship so I'm looking forward to spending one more season in Baton Rouge playing for Coach Saban and LSU."
Webster was a consensus First Team All-Southeastern Conference selection for the second straight year after ranking second in the league with seven interceptions in 2003. He also earned SEC Defensive Player of the Week following LSU's 17-10 win over Georgia in September after picking up nine tackles, one interception and breaking up five passes against the Bulldogs.
During his career, Webster has played in 39 games with 19 starts. He ranks second in LSU history in interceptions with 14, including a school-record tying three in the win over Florida in Gainesville in 2002.
Webster started his career as a wide receiver, playing 12 games at the position in 2001. In his only season as a wide receiver, Webster caught seven passes for 74 yards.
"Obviously we are very pleased and happy that Corey has decided to return to LSU for his senior season" LSU coach Nick Saban said. "We're excited that Corey is returning because he's an outstanding football player, but he's also going to graduate this summer.
"By coming back, Corey will have a chance to continue to develop as a football player and he certainly should have a chance at winning the Jim Thorpe Award as the nation's top defensive back next season."