Britain's economic future will be "compromised" unless more students study science and foreign languages, the director general of the CBI fears.
More languages and science students are needed, it is claimed
Sir Digby Jones issued his warning as pupils across the country wait to receive their exam results this week.
The CBI says the number of people taking A-level physics, as well as French and German has plummeted.
Meanwhile, there are calls to make A-levels harder as a record number of top grades are expected this year.
More than 260,000 students get their results on Thursday and experts predict the pass rate will rise to nearly 97%.
CBI figures show the number of teenagers taking A-Level physics had dropped by more than half in the last 20 years.
They show A-Level entries for French and German both fell by nearly a third between 1999 and 2004.
Sir Digby said: "We must change our cultural attitude. We are an island race but must embrace the world and speak its languages if we want to be in the pole position for business.
"These issues must be tackled by government, teachers, careers advisors and companies - we cannot allow it to blight the UK's future economic success."
The figures also show "very few" students are taking languages crucial to the UK's future economic success such as Mandarin, Russian or Spanish.
Sir Digby said: "Youngsters need to be equipped with the skills to make their way in the competitive globalised economy of the 21st Century."
David Hart, general secretary of the National Association of Head Teachers, said: "I strongly agree with the CBI.
"We need more candidates in languages, single sciences and maths because that is what the country needs."
The Secondary Heads Association also echoed the CBI's concerns.
However, a spokesman for the Department for Education and Skills, said: "The sciences continue to be amongst the more popular courses at A-level and the most recent set of UCAS figures show applications for science subjects up by over 10% compared with last year."
He added: "In 2004, 15,000 more pupils obtained a good GCSE (A*-C) in modern foreign languages than in 1997.
"This government is committed to increasing the take up of languages at all levels of education through its Modern Foreign Languages Strategy."
Despite repeated claims exams have become easier, the DfES said results showed standards were being maintained.
Professor Alan Smithers, director of the University of Buckingham's Centre for Education and Employment Research, said the A-level pass rate last year was 96%, compared to 68.2% in 1982.
In 1982, only 8.9% of students scored grade A at A-level but last year 22.4% achieved it, research has shown.
Prof Smithers said: "It would be reasonable to suppose that we are going to get quite close to 96.5% this year," he said.
One explanation was that pupils took AS-levels in their first year of A-levels, allowing them to identify their best subjects for the next year, Prof Smithers said.
Those changes had given "a tremendous boost" to pass rates but "it probably means we need to put some more difficult questions in", he said.