Fox Sports first reported that the Dolphins would hire Tannenbaum to a senior front office position.
Tannenbaum served as general manager of the New York Jets from 2006-2012. He was fired by owner Woody Johnson after a 2012 season that saw the Jets go 6-10, and he has since been working as an agent for coaches.
His new position in Miami will begin on Feb. 1, according to NBC's ProFootballTalk. Tannenbaum will handle football administration and report directly to owner Stephen Ross. General manager Dennis Hickey will report directly to Tannenbaum and will continue to have control of the 53-man roster.
Fox Sports reports that Tannenbaum is expected to continue representing his clients -- which include Seahawks defensive coordinator Dan Quinn, who has recently interviewed for multiple head coach positions -- until the end of their candidacies.
Tannenbaum and Dolphins executive vice president of football administration Dawn Aponte previously worked together in New York's front office.
The Dolphins went 8-8 in 2014, missing the playoffs for the 12th time in 13 seasons.
- Molly Geary