Millions of workers, including public transport staff, bankers and teachers, have been urged to take part by trade unions and social groups.
Protesters are taking a stand against the president’s proposed pension reforms.
President Michel Temer says the changes are needed to overcome a recession.
“It is going to be the biggest strike in the history of Brazil,” said Paulo Pereira da Silva, the president of trade union group, Forca Sindical.
Demonstrations are taking place across the country, with organisers saying they would focus attention on disrupting cities rather than small towns and rural communities.
Participants are opposed to the government’s pension overhaul, which will be voted on in Congress next week and which could set the minimum retirement age at 65 for men and 62 for women. Public sector workers have been able to retire at much earlier ages.
A congressional bill to weaken labour laws also progressed earlier in the week, and the country is experiencing an ever-unfolding corruption scandal, which has been linked to many top politicians, fuelling further public discontent.