Warwick, 32, can also play at full-back or centre, and he enjoyed a successful stint with Munster before heading to Paris.
"Paul is a winner, very serious about his rugby and very competitive," Worcester head coach Richard Hill said, after securing Warwick's services from next season.
"I want players here with a winning mentality.
"That's not just a phrase you throw about - you have got to do something about it to achieve it. You have to study the game and your own performances to get better and truly push yourself.
"Paul wants to win rugby matches, and that mentality and professionalism is massive."
- Sports & Recreation