Adam Afriyie spoke out as a consultation on the hike proposed by the Independent Parliamentary Standards Authority came to an end.
Hundreds of people have written to Ipsa to express their views, with many understood to be members of the public angry at the prospect of an above-inflation pay rise for MPs at a time when the Government has imposed a 1% ceiling for public sector workers.
The increase from £67,000 to £74,000 will go ahead automatically on September 30 unless Ipsa announces a change in its recommendation in response to the consultation before that date. A spokesman said it would take some weeks to assess the contributions received.
Prime Minister David Cameron has urged the watchdog - set up after the expenses scandal of 2009 to take the final decision on pay out of MPs’ hands - to think again. And a number of MPs, including Labour leadership frontrunners Andy Burnham and Yvette Cooper, have said they will donate any additional income to charity.
But Mr Afriyie warned that a failure to offer MPs competitive salaries risked making Parliament the preserve of the wealthy.
The Windsor MP told BBC2’s Victoria Derbyshire Show: “At the moment, we have about one in four MPs who are either millionaires or have wealthy spouses, inherited homes or trust funds.
“I come from a tough background. I don’t want to see Parliament stuffed with multimillionaires or bachelors who don’t have families to take care of. I think that would be a very bad thing for British politics.”
Mr Afriyie, who chaired the Commons Members’ Expenses Committee in the last parliament, said the rise was part of a package of changes to allowances, pensions and salaries which would leave MPs worse off overall.
“The MPs’ package has gone down and down and down - this is the reality - since 1911, when the payment was first introduced,” he said.
But Labour MP John Mann told the programme: “Parliament has decided to back the Government so everyone else in the public sector is on a 1 per cent increase, so why should MPs get more than that?
“In my area, virtually all the people get paid less than me and if I stood down, there would be a long queue of people wanting to replace me.”