The Daily Telegraph reported that business leaders were being offered the chance to buy tickets at up to £1,000-a-plate to a fund-raising dinner at the Tory Party Conference in October.
The paper said Chancellor George Osborne was being advertised as the guest of honour at the event which will be held at Birmingham International Conference Centre.
The Tories defended the event, saying that both Labour and their Liberal Democrat coalition partners were planning similar fund-raising dinners.
However a former chairman of the Westminster anti-sleaze watchdog branded the move as "unwise" saying it created an impression that it was possible to buy influence in government.
Places for the event start at £500 - with tables for 10 on sale for £5,000 - with each table being hosted by a "prominent Conservative MP", according to a conference guide.
For those business leaders who are prepared to pay out £1,000 for a place, there is a promise that they will get to dine with at least one serving Government minister.
A Tory Party spokesman said: "Under the current system, events to raise money are vital to pay for the running of the party, as they always have been for all political parties."
However Sir Alistair Graham, a former chairman of the Committee on Standards in Public Life, said the arrangement was "unwise" as it "gives the impression you can buy the opportunity to influence government".
"If you're trying to set a high moral tone, this sort of thing is unwise," he told The Daily Telegraph. "Governing parties need to be very careful about their fund-raising. The public reacts very strongly to the idea that you can buy influence with government."