Andy Lynch has signed a two-year deal with Castleford after being released from the final year of his deal at Hull.
Lynch, 33, played 137 games for the Tigers between 1999 and 2004, before moving to Bradford, and has spent the past two seasons at the KC Stadium.
Coach Daryl Powell said: “Andy is a model professional who will help to set the standards alongside the other senior players that we already have at the club.
“He is big and strong with a quality all round game to go alongside his key leadership skills.
“He is also a player who is highly regarded within our club by fans and players alike.
“I am delighted that he be will joining us next season.”
Lynch was an ever present for Hull last season, and has made 28 appearances this year.
His last game was the Challenge Cup final defeat to Wigan, although he is in the 19-man squad for tonight’s play-off clash with Huddersfield.
He said: “I think it’s great that I’m coming back to Cas next year; it’s something that I’m really looking forward to.
“Danny Orr had a big influence on me coming back – I’m good friends with him and he’s been on at me for a while.
“I’ve spoken to Daryl and he’s got big plans for the upcoming season and beyond too.”