Tony Pulis signed Owen on a free transfer on a 12-month pay-as-you-play contract, following his release by Manchester United this summer.
"In terms of goalscorers, Michael Owen is up there with Robbie Fowler and Alan Shearer, and I would put Ruud van Nistelrooy into that category as well," said Delap.
"That sort of natural talent is hard to coach into someone. He has always been a yard ahead of people with his brain, not just his pace.
"He's a natural goalscorer and players don't lose that. They might lose a yard of pace, but that natural instinct to score goals will still be there."
Owen has yet to make his debut for Stoke, though he could be in contention to make his first start against Manchester City.