Congress of South African Trade Unions (Cosatu) general secretary Zwelinzima Vavi's salary has doubled this year to R500 000 a year, The Star newspaper reported on Wednesday.
"My salary doubled because we were losing all the policy capacity in the federation," said Vavi.
"The economists and accountants were all gone, because if you keep the salary at R250 000, it means the economists can't make those sacrifices for years and years. They lose out."
The newspaper said Cosatu administrators and researchers earned about R7 000 per month while security guards earned less than R4 000.
Vavi said several staff members in "economic" positions received 100% increases this year.
But the lower earning staff received only 15% wage hikes, reported the newspaper.
Vavi has been very vocal in his criticism of South African Communist Party leader Dr Blade Nzimande, who as Higher Education and Training Minister, recently bought himself a R1-million car.