The 30-year-old international front rower joins the Wildcats on one-year contract.
The Wildcats players reported for training last month and Paul King is expected to join his new club-mates this week.
John Kear, the Wildcats’ Head Coach, said: “I’m delighted that Paul has agreed to join us. I worked with him when I was coach at the KC Stadium and have a great deal of respect for him, both as a man and as a player.
“He’s a very experienced player who has appeared at the highest levels of the sport and will be a valuable addition to our squad for next year.
He added: “Given the competitive nature of the engage Super League, it is important that we’re able to call upon experienced players like Paul King so that we can blend in the younger players at the right moment and provide them with the appropriate kind of leadership”.
During his time with Hull he won a Challenge Cup winners’ medal (2005) and was a Super League Grand Finalist in 2006. He played once for Great Britain and once for England, both appearances coming in 2001.
Paul suffers from claustrophobia but is able to carry on a normal life thanks to the support he receives from his family, friends and club mates.
Kear continued: “Paul’s a quality player with a shrewd Rugby League brain. He’s still got plenty to offer in Super League.”