Mark Henry Washington (born December 28, 1947) is an American former professional football player who was a cornerback in the National Football League (NFL) for the Dallas Cowboys and New England Patriots. He played college football for the Morgan State Bears.

Washington attended Chicago's John Marshall Harlan Career Academy, before receiving a football scholarship to play for Morgan State University. He was coached by Earl Banks, who at the time sent many of his players to professional football.

He became a four year starter at cornerback and was part of a team that had 31 straight wins. As a senior, he was named co-captain, posted 6 interceptions and received All-CIAA honors. He finished his career with 15 interceptions.

In 1993, he was inducted into the Morgan State University Athletic Hall of Fame.

Washington was selected by the Dallas Cowboys in the 13th round (335th overall) of the 1970 NFL draft. Even as a rookie, he was one of the best athletes on the team and showed his big play potential with a 100-yard kickoff return for a touchdown against the Washington Redskins. He also blocked an extra point in Super Bowl V. His 48.4 yards per kick return that season remains a franchise record (though unofficial, as he only returned five kicks on the season).

Coming into his second year, he injured his knee while returning a kickoff in preseason and was waived injured on August 25, 1971. He would eventually rejoin the team and play in two games.

When Herb Adderley retired in 1973, he had a chance to earn the left cornerback starting job, but he was passed over by Charlie Waters.

In 1974, he was named the starting left cornerback at mid-season after Waters struggled and held the job until being slowed down by an ankle injury in the last 2 contests, starting a total of 6 games.