Hurd claimed that a proposed run of seven seasons "isn't nearly [long] enough" for the zombie drama, in an interview with Daily Dead.
"I think much bigger and maybe it's [because of] my feature film background," she said. "Seven isn't nearly enough."
She continued: "There is so much rich material to draw from and so many fantastic characters. There are so many different situations and characters to join our survivors, as well as [characters] to be pitted against them… I think there is no limit."
Hurd added that Robert Kirkman - creator of the original Walking Dead comic - is still devising new characters and storylines.
"There is certainly no limit to the comic book series," she claimed. "Robert has probably 250 [issues] figured out."
A third season of The Walking Dead will premiere in the UK on FX and on AMC in the US later this month. A fourth season is rumoured to be in the planning stages, but is yet to be officially confirmed.
> Norman Reedus Walking Dead Q&A: 'Season three blows last year away'
> Danai Gurira Walking Dead Q&A: 'We've kept a lot of who Michonne is'
Watch a promo for the return of The Walking Dead below: