McKenzie has 15 years of NFL personnel experience. The former NFL linebacker was the Green Bay Packers' director of player personnel for eight years.
The Raiders hired McKenzie as the franchise's general manager in 2012. He won NFL Executive of the Year in 2016 after Oakland went 12-4 and almost captured the AFC West title.
Two years later, the Raiders fired McKenzie in December after seven seasons with the team.
The Dolphins' latest move continues their offseason coaching and front office overhaul. Miami fired head coach Adam Gase following the season and hired former New England Patriots assistant coach Brian Flores as his replacement.
Dolphins general manager Chris Grier now oversees football operations and reports directly to team owner Stephen Ross. Executive vice president of football operations Mike Tannenbaum was assigned a different role in the organization.