The former Rangers captain is headed to Bristol.
ESPN/ABC and Turner will take over NHL coverage from NBC beginning next season after the two companies reached blockbuster deals with the NHL earlier this year.
Callahan, 36, could be part of the studio and game reporting, according to the report. He has done some work for NBC and the NHL Network since retiring.
Callahan spent eight seasons with the Rangers. He will join Ray Ferraro, Brian Boucher, Steve Levy and Sean McDonough on the growing team of hockey analysts at ESPN/ABC.
Turner has reportedly hired Kenny Albert and former Rangers forward Eddie Olczyk to lead its hockey team.