Smith was drafted by the Pittsburgh Steelers in the 4th round, 109th pick overall, of the 1999 NFL draft. Smith played in every Steelers' game at left defensive end from 2000 through 2006. Smith has been considered an ideal defensive end in Pittsburgh's 3-4 defense. Smith won a Super Bowl ring with the Steelers in Super Bowl XL, during the 2005 season. He recorded four tackles throughout the game. After the 2008 season, Smith won another ring with the Steelers in Super Bowl XLIII.