The one-year deal is for $2 million, a league source told ESPN NFL Insider Adam Schefter.
Sheppard's deal was done on Wednesday, bringing a nine-year veteran and two-time Pro Bowl pick to a group of cornerbacks including starters Griffin and Antoine Winfield and backups Benny Sapp and Asher Allen. Griffin got hurt in the NFC Championship Game and might not be ready for the start of the season.
Sheppard played seven seasons with Philadelphia, the first four while Vikings head coach Brad Childress was the Eagles' offensive coordinator. Taken in the first round by the Eagles in 2002 out of Florida, Sheppard had a career-high six interceptions in 2006. He has gone to the playoffs in six of his eight seasons.
"Lito is a great guy who fits what we are looking for," Childress said. "He's the type of person and player we value at the cornerback position."
Sheppard was let go by the New York Jets last month after one disappointing, injury-impacted season with the team. The Jets acquired him in a trade, but he started only nine games and was benched for the AFC Championship Game. Sheppard was bothered by quadriceps injuries and finished with 31 tackles, one interception and eight passes defended in 11 regular-season games.
Still, Sheppard has made big plays. He has returned three of his 19 career interceptions for touchdowns and was the first player in NFL history with two such returns of more than 100 yards.
Information from The Associated Press was used in this report.