Professor Chris Husbands, director of London University’s Institute of Education, said a shortfall of 6,000 teachers could leave schools in a “bad place” next year.
Figures from the Department for Education (DfE) show there are 38,900 places allocated for post-graduate training programmes and the government’s School Direct scheme this year.
But just 32,950 student teachers have been accepted so far, leaving a shortfall of almost 6,000.
Answering questions at an all-party House of Commons Education Select Committee hearing, Prof Husbands said he feared a teacher shortage was imminent.
“I think that we already have a serious problem,” he told MPs.
“Ten out of 13 secondary subject lines are failing to meet the allocations this year. The shortfall in maths and physics is a very serious problem. Biology has failed to recruit to its allocation and that has not happened for several years.
“As a system, it can take a one-year hit, but if we’re here in the same place next year then we’re in a bad place.”
However, David Laws, the schools minister, told the committee that the government had over-allocated places this year, so that good candidates in vital subjects such as maths and physics were not rejected through a lack of places.
He added that schools had been “very choosy” about the people they accept for training.
The DfE figures show that
43 per cent of physics places on School Direct and university-based training courses are unfilled this year, while maths is seeing vacancies of 22 per cent.
Other subjects with shortfalls include modern and ancient languages (10 per cent), computer science (37 per cent), music (12 per cent), business studies (16 per cent), religious education (24 per cent) and social studies (66 per cent). But chemistry, English, history and PE courses have over-recruited.
Overall, 9,580 places have been allocated through School Direct, with 6,360 people being accepted so far – a shortfall of around a third.
About 29,320 places were available through university-based training courses, with 26,590 people accepted.
Mr Laws said that the government was targeting 34,470 recruits, which means the shortfall against its official target is just 1,520.
Prof John Howson, teacher recruitment expert and head of Data for Education, said: “We could be looking at the worst outcome for teacher supply for more than a decade.”
Stephen Twigg, the shadow education secretary, said ministers had “botched” teacher training. He added: “They are totally out of touch with the high standards that parents want to see in our schools.”
The Association of Teachers and Lecturers, which has been carrying out its own surveys on the take-up of places on School Direct, said the latest figures were “extremely worrying”.
Nansi Ellis, assistant general secretary, said: “This government has complicated teacher training to such an extent that it can’t keep a timely track of the number of teachers applying for places, which hinders its ability to plan for current and future staffing needs.
“We need to be reassured the government knows how many teachers are needed for each subject and part of England, and has a plan to ensure the demand can be met.”