President Jacob Zuma and delegates of the Congress of South African Trade Unions' (Cosatu) congress have started to arrive at the Gallagher Estate in Midrand on Monday.
The four-day gathering is held every five years.
Cosatu general secretary Zwelinzima Vavi said he is not nervous about the congress, which will be the most important of his political career so far.
The ANC's proposed job seekers grant is high on the agenda of the conference.
The grant was proposed at the ANC's policy conference in June, but the trade union federation wants more details.
It is not clear where money for the grant will be sourced or who will handle how it is spent.
In his political report, Vavi said the federation should discuss whether the new grant will discriminate against job seekers based on their age.
He said to limit the age of those who qualify for the grant, the way government's proposed youth wage subsidy does, will be unacceptable.
Cosatu is against the implementation of the youth subsidy, saying it will incentivise companies to retrench older workers in order to create jobs for younger staff.
Vavi also said the conditions attached to the grant must be reasonable and not lead to situations where workers are coerced into taking unacceptable work.
He said if these matters were addressed satisfactorily, it will be a step forward to comprehensive social protection.
Cosatu is historically a supporter of the basic income grant.
Zuma has said government cannot afford to keep increasing social grants.