The Conservatives would offer students cash incentives to study maths, science and languages, Michael Howard says.
The proposals are aimed at tackling a skills shortage
A £2,000 bursary should be given to students of key subjects in which numbers are falling, the Conservative leader told a meeting in Cambridge.
The action is needed to tackle the UK's shortage of scientists, mathematicians and linguists, he said.
The money would be given to students in England on graduation, not at the start of their university courses.
The government says the Tories' plans "do not add up".
Scientists and business leaders have warned that Britain will lose its place
as a world leader in research and industry if the decline in some subjects continues.
Some universities already offer bursaries to students studying particular subjects.
And the idea of centrally-funded bursaries for maths was suggested in an official inquiry into maths teaching earlier this year.
In a speech at Emmanuel College, Cambridge, Mr Howard said: "If our universities are to continue to be centres of international excellence, then we must protect in particular some of the core subjects on which that international excellence depends.
"In too many institutions, the future of those core subjects is under
"We will fund 10,000 bursaries specifically designed to attract more able young people to study our key sciences and to help reinforce the base of scientific expertise in this subject."
The Conservatives said the savings would come from halving the administration budget of the Higher Education Funding Council for England, saving £8.4m.
Other savings would be made by reducing the "overbearing" higher education quality assurance system and scrapping the new access regulator, Offa.
Earlier this year, the Institute of Physics announced it was offering £1,000 a year to those taking physics degrees.
In September, Education Secretary Charles Clarke said he wanted a "national debate" on whether certain key subjects should be protected in the national interest.
He said he was asking Cabinet colleagues to come up with ideas for which subjects would need extra support.
Liberal Democrat education spokesman Phil Willis said: "Michael Howard is tackling the problem far too late. He promises money to those who already have a strong interest in these subjects.
"By the time they reach university, many young people have long given up on maths and science."
For the government, Chief Secretary to the Treasury Paul Boateng said the Tories' plans did not add up.
"The gaping holes in Tory plans have widened this week. None of their plans add up. They could only pay for this week's commitments by making deeper and more severe cuts to other public services," he said.