The running back follows 2021 Ring of Honor inductee quarterback Matt Hasselbeck and former head coach Mike Holmgren.
Alexander is the only Seahawk in team history to earn NFL MVP honors (2005). He will be inducted during Seattle's game against the Arizona Cardinals on Oct. 16.
Alexander will become the 15th player to enter the Seahawks Ring of Honor.
"Shaun is the true definition of a champion both on and off the field, and we are excited to formally celebrate him in front of the 12s this season with his induction ceremony," said Seahawks president Chuck Arnold told Seahawks.com.
Alexander was also named to the NFL's All-Decade Team for the 2000s and was the team's nominee for the Walter Payton Man of the Year in 2005.
He rushed for 1,000 yards for five straight seasons averaging 19.6 touchdowns per season during that time.
Other members include Steve Largent, Jim Zorn, Dave Brown, Pete Gross, Curt Warner, Jacob Green, Kenny Easley, Dave Krieg, Chuck Knox, Cortez Kennedy, Walter Jones and Paul Allen.