England's hat-trick hero of 1966 feels Rooney has been at the peak of his powers this season, but the former West Ham star warned it is of paramount importance to keep the Manchester United star fit for the duration of the tournament.
"Rooney is the one player that England cannot afford to be without," Hurst told Press Association Sport. "Wayne, with the season he has had for Manchester United and England, needs to be playing. That would certainly be the case for the latter part of the tournament. You could get away with it in the early rounds, maybe, but to win it, you need your best players for the latter stages.
"He gives you that x-factor. He is one of the top players in the world now. He is at his peak and that is hard to replace. You can't replace great players playing at their best. It is impossible," he added.
Hurst also backed Rooney to lead the line on his own if necessary. "I think there is a strong case for playing Rooney up front on his own like he does for United," he said. "I am not sure whether he could have done that a couple of years ago but he has proved he can do it and score goals."
A trip to the last four
Hurst believes it would be a major disappointment if England fail to reach at least the semi-finals for the first time in 20 years, and feels it is time for the team to finally live up to their potential. "It is hugely disappointment that we haven't been closer to winning the World Cup than we have in 40 odd years, very disappointing," he said.
"I will be very disappointed, if we keep the team together and remain injury-free, if we don't get at least to the semi-final. Anyone can get to a quarter-final. We've been there a couple of times. We are well-managed now, there is a lot of discipline in the squad."
But Hurst conceded: "The big argument is: have we enough players in the squad to win six or seven games? We are capable of making the last four and, when you get to that stage, you are in the lap of the gods. You are up against the big boys - Spain, Italy and Brazil - and then you need an ounce of luck.
"On a one-game basis, we are capable of beating anyone in the world. But it is important that we keep our best team on the field because our squad is not that strong and you have to take into account injuries and suspensions. Apart from Rooney, you can't afford to lose a Steven Gerrard or a Frank Lampard. If we don't, we have got a chance," he finished.
Hurst, who was spotted by West Ham playing Sunday football in the Tandridge League, is an advocate for non-league football and its role in the development of the English game.