Pittsburgh defensive back Ron Woodson, who like Smith was eligible for the first time, also was inducted with linebacker Derrick Thomas, guard Randall McDaniel and Dallas wide receiver Bob Hayes.
The 2009 class brings the total inducted to 253.
Smith, the Bills' first overall pick in the 1985 draft, holds the NFL record for sacks with 200. He played in 11 Pro Bowls.
Thomas spent all his 11 seasons playing for Kansas City and had more sacks during the 1990s than any other player.
McDaniel was an all-pro nine consecutive seasons in a 14-year career with Minnesota and Tampa Bay.
Hayes won two gold medals in the 1964 Summer Olympics before bringing his speed to the NFL. His 71 career touchdown catches remain a Dallas Cowboys record. Hayes died in 2002.
Wilson founded the Bills in 1959, won two straight American Football League titles in the mid-1960s and his team is the only one ever to play in four straight Super Bowls. He played a key role in the success of the AFL and its merger with the NFL.