The Bristol-born ace, a member of the senior England squad during the 2012 RBS Six Nations, has played 84 games for Quins - scoring five tries - after joining from Bath Rugby in 2007.
Brooker was previously part of the England Under-21 Grand Slam winning team of 2006, featuring in the IRB Junior World Championships in France, and represented England Saxons in 2012.
Worcester boss Dean Ryan admitted he was delighted to sign the talented front row forward and thanked Harlequins and his counterpart Conor O'Shea for allowing Brooker to make the switch.
"We are very pleased to be able to sign a player of the experience and calibre of Chris. He will add greatly to the squad we are assembling ahead of the new Aviva Premiership campaign," said Ryan.
"Chris comes to Warriors eager to re-launch his career, now he is fully recovered after being sidelined with a knee injury, and his appetite and desire will be evident to all.
"He is determined to be a success at Sixways and wants to perform not only for Worcester but also return to the form that brought him to the attention of England and push his internationals aspirations."
Brooker added: "I'm excited about becoming a Warrior. It's a new coach, new start and a new club for me.
"I want to come back and really impress, get back to where I was before I got injured and I truly feel this is the club to do that under the guidance of Dean Ryan."
Join Chris Brooker and Worcester Warriors for the 2013/14 season at Sixways! Season Tickets are on sale NOW by calling the Warriors Box Office on 01905 454183 or clicking HERE for more information.