The Charity Commission is to cut 60 jobs by March next year.
The latest round of redundancies means that the regulator will have shed 178 posts in six years.
The cuts, which will take total staff numbers down to 425, were announced in chief executive Andrew Hind's report for the commission's open board meeting on Thursday.
"This is extremely challenging at a time when the demands on the commission, and the importance of the charity sector, have never been greater," he said.
Hind said that the commission faced a £900,000 reduction in its funding for 2010/11 and its budget in real terms was £5.5m less than in 2005/06.
"I have to say that the commission cannot deliver all its present services and functions and, at the same time, absorb further significant funding reductions," Hind concluded.