Applicants to Oxford might in future apply to the university rather than to individual colleges, it is proposed.
The number of applications to Oxford University is consistently rising
A working party on selection and admissions recommends a single body to handle all undergraduate applications.
The university said its admissions policy had been working well, but could be improved further.
Latest figures show that the proportion of students accepted from state schools is down by more than one percentage point this year.
Chairman of the working party, Sir Tim Lankester, President of Corpus Christi College, said the university's applications procedure was rigorous, but could be improved by the proposals.
"The aim of the changes we are recommending is to provide further assurance that - with more and more good candidates relative to the available places - we have a process which is both efficient and effective," he said.
The proposals are designed to ensure "maximum consistency" in the admissions process.
But the proposals would keep admissions in the hands of current subject tutors and would not alter the autonomy of colleges, Sir Tim added.
The working party proposed two application models.
Under the first model, offers could be made by all tutors in each subject, and all successful applicants would be offered a college place. After being accepted, students would have the option to express a college preference.
Under the second model, candidates could continue to state a college preference when submitting their application, with those shortlisted for interview then interviewed by tutors at two colleges.
In 2003, 51.7% of the UK intake at Oxford was from state schools - this rose by one percentage point to 52.7% in 2004, but dropped to 51.3% this year.
Applicants from the state sector have increased by nearly 40% in the last six years - from 4,177 in 1999 to 5,809 in 2005.
This trend matches the continuing increase in overall applications, which have risen by over a third in 11 years to 12,496 this year.
Overall the university receives around four applicants for every place.
A spokeswoman for the university said such a drop in the proportion of state school applicants accepted was not a cause for concern.
"The figures are really very similar to last year and we don't think a small fluctuation year on year is significant," she said.