Campbell, 39, will serve as an assistant head coach and tight ends coach for the Saints, according to ESPN's Mike Triplett. Campbell was rumored to be in the discussion for San Diego's offensive coordinator gig before the hire.
The Saints are also bringing in former Detroit Lions offensive coordinator Joe Lombardi to be the quarterbacks coach.
The National Football Post previously reported that the Minnesota Vikings and Dallas Cowboys were also interested in Campbell. Campbell left the Dolphins officially on Wednesday, according to the Palm Beach Post.
Campbell, a former NFL tight end, marched the Dolphins to a 5-7 record as interim coach after the firing of Joe Philbin. He joined the Dolphins as a coaching intern and offensive assistant in 2010 after an 11-year playing career with the New York Giants, Cowboys, Lions and Saints.