Tim McKyer was born in Orlando, Florida and raised in Port Arthur, Texas, graduating from Lincoln High School in 1982. He went on to play football at the University of Texas at Arlington.
 
Drafted by the San Francisco 49ers in the third round in 1986, McKyer played with the club for three seasons. He was chosen All-Pro in both 1988 and 1989. McKyer was also part of the 1988 and 1989 San Francisco 49ers Super Bowl championship teams. During the 1989 season, he led the team's secondary in interceptions, with seven. McKyer moved to the Miami Dolphins in 1990 but remained for only one season.
 
The outspoken back was credited by coach Don Shula with helping Miami reach the playoffs for the first time since 1985, but McKyer felt he had "no relationship" with the coach.
 
He was traded by the Dolphins to the Atlanta Falcons in 1991 for third and 12th round draft picks. McKyer stayed with the Falcons through the 1992 season and then moved to the Detroit Lions.
 
After his tenure with the Lions, McKyer played with the Pittsburgh Steelers, the Carolina Panthers, and the Denver Broncos. During his final season in 1997, McKyer won his third Super Bowl, this time with the Denver Broncos.
 
In addition to his athletic ability, he is appreciated, in Port Arthur and elsewhere, for his work with schoolchildren and for the endowment of a scholarship in the Port Arthur Independent School District.