Mazzilli, who was fired by the Baltimore Orioles on Aug. 4, 2005, formerly was the Yankees' first-base and outfield coach from 2000-03 and will be the team's bench coach in 2006.
"Lee was certainly qualified for this position before he had been a major league manager and he's only that much more capable now," Manager Joe Torre said on the club's Web site. "He knows the game and he knows New York. I look forward to his presence in the dugout."
In a 14-year career, Mazzilli played for the Mets' World Series champions in 1986, Texas, Philadelphia, Pittsburgh and Toronto. He was an all-star in 1979, and began his coaching career as manager at Class-A Tampa in 1997.
Mazzilli is the second former manager to join Torre's staff this week. Larry Bowa was named third base coach on Monday.