Debbie Jevans made the comments after a tweet by World Rugby chief executive Brett Gosper said an early England exit was "not what they wanted to hear".
Jevans would be "very upset" if England failed to make it out of their group but not in an official capacity.
"From our perspective it doesn't make a difference," Jevans said.
"Of course you think about it when you look at the tough group England are in and the impact that may or may not have, but I think our job as an organising committee is to make sure that we deliver an event that is the best it can be."
The 48-match tournament begins on 18 September when England play Fiji at Twickenham.
Stuart Lancaster's side are also in the same pool as Australia, Wales and Uruguay and only two will make it through to the knockout round.
Wales head coach Warren Gatland, whose side are in the same group as England, said he was "surprised" by Gosper's comments.
Jevans says she would like an England versus New Zealand final but claims the tournament's success does not hinge on the hosts' performance.
"Our focus is not about who wins or is in the final," Jevans added.
"From a delivery perspective we are genuinely looking at it as delivering for 20 teams and making sure they can all compete to the best of their ability.
"Our biggest selling ticket so far has been Argentina v New Zealand so I am not at all concerned about England being the sole focus of the Rugby World Cup."
The chief executive of England's World Cup organising committee wants the hosts to make the knockout phase but says it's not essential for the event.