The 28-year-old England international stand off half joins the Wildcats on a deal which lasts until the end of the 2010 season.
Cooke is one of the largest halfbacks playing in the modern game as he is 6ft 5ins (1.96m) tall and weighs in at 16stones (102kg).
John Kear, the Wakefield Trinity Wildcats Head Coach, said: “Paul Cooke is one of the most gifted players of his generation and we’re delighted that he has signed for the Wildcats.
“Paul is very versatile because he can play at loose forward if it becomes necessary and that’s a great option to have available for any Super League club.
“I worked with Paul when I was on the coaching staff at Hull FC so we know each other well. I’m a great admirer of his skill set and also recognise the great talent he has for playing Rugby League.
“He’s the kind of player who makes other players play well and that’s a special quality we can use at the Hearwell Stadium.”
Paul Cooke said: “I’m delighted to be joining Wakefield Trinity Wildcats and working with John Kear again.
“The Wildcats have shown some great form in 2010 and I’m looking forward to joining an exciting team.
“I’d like to thank everybody at Hull KR, the players, staff and, particularly, the fans for all the support they’ve given me while I’ve been at Craven Park.”
Cooke started his professional career with Hull FC in 1999 and played 204 games in black and white before moving across to arch rivals Hull Kingston Rovers in a high profile deal in 2007.
Since moving to Craven Park Paul has played 65 games for Rovers.
A Hull KR statement read: “Hull Kingston Rovers have today unconditionally released Paul Cooke from the remainder of his contract. We wish Paul all the best for the future and would like to thank him for his contribution over the last three years.”