Haskell previously spent seven seasons with Wasps and is now relishing a return to action against Leeds Carnegie on Friday.
"I was always a fan of Wasps as a child and I always wanted to come back here. I feel a lot more mature now and am enjoying doing some work with some of the young guys as well and I am excited to just be here," said Haskell.
The former England international hopes that his Premiership comeback can also help reignite his international career.
"If Wasps go well you always have a chance to get your England place back and that's what I want to do."
Haskell was a fringe player for England at the 2011 Rugby World Cup.