The National Union of Mineworkers (NUM) expressed disappointment on Tuesday about the appointment of Mark Cutifani as Anglo American's new CEO.
The company had failed to appoint either a black or even a white South African woman to lead the global mining company, NUM general secretary Frans Baleni said.
The union also accused Anglo of giving top jobs to foreigners - Cutifani is Australian - and of overlooking qualified locals.
"The mining sector remains lily-white at the top and at board level, with a sprinkle of black here and there... Those who work underground are black and poor, but those in higher offices are white and male."
Baleni said Cutifani's appointment reinforced the notion that leadership and management in the mining sector still belonged to the "old boys club".
Anglo American spokesperson Pranill Ramchander said the job had been given to the best candidate.
"His appointment was based on his experience."
Ramchander could not comment on whether there was any female or black candidate with the same skills and experience as Cutifani.
The NUM called on Cutifani to make changes at the company.
"We urge [him] to show commitment to transformation, as well as introduce the global framework agreement to ensure the standardisation of conditions of service," Baleni said.
Cutifani, who is CEO of mining company AngloGold Ashanti, will take office at Anglo American in April, succeeding Cynthia Carroll, who resigned last year.