The former Wales international has enjoyed a hugely impressive spell in London as he played over 200 games for Quins and became a firm fan's favourite.
However, he will now make the move north to link up with the coaching team of Richard Hill and Phil Davies and has spoken of his desire to bring real success to Warriors.
"Worcester is a club that has strong traditional values and I want to bring success," said Jones. "I want silverware and I wouldn't come to Warriors if I didn't think that was possible in the future.
"It's a very forward-thinking club and I've been to look at the facilities and was very impressed with the set-up.
"The coaching team at the club and squad that is being built is something really exciting and I can't wait to get there and get started. Hopefully that will be in the Premiership and we can do big things.
"I was coached by Hilly for about a year when I was at Newport, before I came up to join Harlequins, so I look forward to playing for him again and Phil Davies, who I have been very impressed by," he added.
"The move to Worcester will also put me closer to home. My family is just across the border in Wales and my four-year-old son is due to start school so we can get him settled too.
"But ultimately this is about rugby and I'm coming to Worcester to stand up and be counted. I want to win trophies, I want to be playing in the Heineken Cup and I want to enjoy that success at Warriors."
Jones has also paid tribute to the staff, players and fans at Harlequins after almost a decade of service and is keen to sign off his time in London in style.
"I have been at Harlequins for nine seasons and it has been a great time that has seen me play in some amazing games," he said. "Hopefully I can still win something this season with Harlequins. I feel we have a very good chance this year and that would be the perfect send-off.
"I have to give a huge amount of credit to the people at Harlequins for the time I have enjoyed there and the brilliant supporters who have always backed me. I look forward to a big end of the season with them now."