While the Raiders did not disclose terms of the deal, a source told ESPN.com's John Clayton it is a two-year contract.
Though he has spent the past seven seasons with the New York Giants, Boothe was drafted by the Raiders in the sixth round of the 2006 draft.
Boothe turns 31 in July and had started the Giants' last 42 games, including all four of their postseason games en route to the Super Bowl title following the 2011 season.
His greatest strength is his versatility, as the Giants have used him at center and guard and he's had no trouble transitioning between the spots.
ESPN.com Giants reporter Dan Graziano contributed to this report.