Students from across the UK gathered in Cardiff on Thursday to march against the possible introduction of top-up fees in Wales.
Protesters chanted slogans and blew whistles during the march
They were lobbying for fees to be ruled out after the next expected assembly elections in 2007.
The Rees Commission, set up to consider university funding in Wales, will make its recommendations in February.
The Welsh Assembly Government said its manifesto commitments ruled out any top-up fees in the academic year 2006/07.
They were marching through the city from Roald Dahls Plass in Cardiff Bay to its finish outside the Wales Office in the civic centre.
James Knight, president of NUS Wales, said: "We are pulling out all the stops to prevent a market being created in higher education.
"This demo will prove the strength of feeling of people across the UK who realise that introducing variable top-up fees in Wales would price many poorer students out of the system altogether."
A spokesperson for the assembly government said: "The Welsh Assembly Government was elected on a manifesto commitment that variable fees would not be introduced in Wales during the lifetime of the second Assembly.
The demonstration gathered at Roald Dahls Plass in Cardiff Bay
"Variable fees will not be introduced in Wales in the academic year 2006/07.
"The education and lifelong learning minister has established an independent review chaired by Professor Teresa Rees, pro vice-chancellor of Cardiff University, to advise on future policy in relation to tuition fees and student support arrangements in Wales.
"The independent panel of experts will submit an interim report on the issue of fees in February, with a final report by April next year."