Actors including Sir Ian McKellen, Kevin Spacey and Joanna Lumley have passed a motion of no confidence in the Arts Council England.
Kevin Spacey was among those who attended the meeting
Some members of actors' union Equity are angry at proposals to cut the funding of nearly 200 organisations.
But the council's chief executive Peter Hewitt said it would be funding 80 new projects, while other organisations would receive more money than before.
A government-commissioned report on arts policy came out on Thursday.
Arts Council England's decisions are in tandem with the government's report, with the focus on excellence rather than targets such as audience size.
But Equity members said consultation over the cuts had been too brief and that the criteria the decisions were based on were not clear.
"Cut funding to our smaller spaces and you eventually starve our larger ones to death," said Van Helsing star Samuel West.
Arts Council England has said it won't make any final funding decisions until the end of the month, according to the BBC's arts correspondent, Rebecca Jones.
The motion of no confidence was passed at a meeting attended by nearly 500 members of Equity.
Some regional theatre programmes are under threat
Addressing the Equity meeting, general secretary Christine Payne welcomed the extra money the government had made available to Arts Council England over the next three years.
But she said the funding process "is not open, it's not transparent, there is no dialogue with the theatre community".
Mr Hewitt said that while the opinions of those attending the meeting were important, "we do not feel they are representative of the theatre community as a whole".
"We must remember that 75% of our funded organisations are getting an increase in line with inflation or above and their voice was not heard at today's meeting."
The government-commissioned report, which relates to all art forms, recommended that:
- All publicly funded cultural organisations remove admission charges for one week each year to encourage those who feel the arts is not for them.
- The 10 most innovative cultural companies receive 10-year funding packages.
- The board of every cultural organisation should contain at least two artists and or practitioners.
- Innovation and risk-taking be at the centre of funding decisions.
- All funding decisions are based on professional judgements of what is and what is not excellent.
Under the current system, arts organisations have to meet targets on criteria including audience numbers and access.
The author of the report, Sir Brian McMaster, said Britain could be "on the verge of another Renaissance".
High profile theatres facing cuts under Arts Council England proposals include the Bush Theatre in London's Shepherd's Bush, widely regarded as a breeding ground for new writing talent.
Playwrights whose works have first been performed at The Bush include Stephen Poliakoff, Conor McPherson, Joe Penhall and Charlotte Jones.
The theatre is set to lose nearly half of its funding. Many regional theatres are also facing cuts.
Mr Hewitt said bad news for some meant good news for others.
"It's incumbent upon the Arts Council to ensure the arts remain energised, to bring in new ideas, new organisations into the arts for the future," he told the meeting.
"And sometimes that does mean that we have to question some of those organisations that have been supported sometimes for a long time," he added.
Sir John Tusa, former managing director of London's Barbican Centre, told BBC Radio 4's Today programme that he welcomed the shift of focus from targets to excellence.
"This is a painful transition, probably not a very well-managed transition, but I suspect it actually has to take place," he said.
Artistic director of the Eastern Angles Theatre Company, Ivan Cutting, said he expected to be judged on excellence but that the Council must take into account that regional theatres deliver "a certain type of show to a certain type of audience".